April Gardening Checklist

/, Gardening Checklist/April Gardening Checklist

April Gardening Checklist

Fellow Gardeners,

The information, dates and techniques in this blog are as accurate as I can currently offer. During the past three decades I have cared for, nurtured and observed tens of thousands of plants. With the help of many gardening friends I have attempted to offer on these pages some useful information to help you with your own garden. Gardening is sharing. Any corrections, comments or suggestions are appreciated and will improve future information.

Annuals:

  • (See also Sweet Peas and Wildflowers)
  • Some of your cool-season annuals may still be going strong, especially along the immediate coast. If so, leave them in. Otherwise, it’s time to replant these with warm-season varieties.
  • Warm-season annuals should be in abundant supply and in all sizes right now. Choices include petunias, lobelia, verbena, marigold, ageratum, cosmos, impatiens, coleus, torenia and begonias.
  • If you are in a warm inland garden this is the first good month for planting the real hot weather sizzlers like dahlias, zinnias, gomphrena, cleome, portulaca and lisianthus.
  • Because of their quick growth and heavy flowering potential, annuals need more fertilizing than most other plants in the garden.
  • Keep deadheading (removing spent flowers) from annuals to help them continue blooming abundantly.

Avocados:

  • Apply your second feeding to avocado trees this month. A mature avocado tree should be given between ½ and 1 pound of actual nitrogen per inch of trunk diameter. (Example: 15-30 pounds of 20% nitrogen if a six-inch trunk; 30-60 pounds of 10% nitrogen if a six-inch trunk, etc.)
  • Avocados are putting on quite a bit of new growth right now and the plants should look at about their healthiest of the year.
  • Don’t be alarmed by a lot of leaf drop on mature plants. Avocados produce a lot of leaf litter nearly year round. This is a normal condition.
  • Irrigate as needed to keep the soil moist, but not wet.
  • This is a very good month for planting avocados. Being sub-tropical plants, avocados prefer to be planted at the beginning of the long warm half of the year.
  • Be sure to keep a very thick blanket of mulch, compost or fallen leaves under mature avocadoes at all times. Avocadoes need a cool root-run for good health.
  • Most varieties will not have fruit ready for harvest this early. However, some varieties, like ‘Gwen’ and ‘Whitsell’ often have fruit at unusual times.

Azaleas:

  • Many azaleas are blooming now. For these blooming plants be cautious of getting the flowers wet from overhead watering or a late season rain. The flowers will turn to mush with water on them, especially pure white hybrids.
  • Azaleas are nearly dormant while they are in bloom, so this is an excellent time to plant them. Since they are also in bloom, the selection is excellent as well.
  • They don’t really require any pruning, but if you do need to shape them or reduce their size a bit as soon as they finish blooming is the best time to do it.

Bearded Iris:

  • Most bearded iris are now developing flower buds or even blooming.
  • Apply another application of a good well-balanced, general-purpose organic fertilizer to them this month and the flower production will be even better. Any fertilizer labeled for roses (by not with insecticides or other added ingredients) will do fine.
  • Trim off the faded flower stalk just above the foliage when the last flower fades.

Beneficial Insects and Wildlife:

  • Eugenia Psyllid (Trioza eugeniae) may likely already be showing signs of damage on the new growing tip of Syzygium paniculata (formerly Eugenia). Try not to spray. The beneficials will be along in a few more weeks and usually do a more than adequate job for free.
  • Giant Whitefly is active again in some gardens, but just starting in others. Predators and parasites may start appearing now also, but remember, they will usually be a month or so behind the whitefly. Check immature whiteflies carefully for indications of parasitation.
  • Many beneficial insects also feed on pollen. Beneficials can be encouraged in your garden by planting a few flowers that they particularly enjoy. These include Yarrow (Achillea), Alyssum, Chamomile, White Clover, Paludosum Daisy, Cosmos, Lantana, Queen Anne’s Lace (Ammi majus) and Centranthus (sometimes called Valerian or Jupiter’s Beard).
  • Ladybugs can be released this month. This is also excellent time to release Lacewings. Two or three releases of both ladybugs and lacewings in the spring can reduce many pest populations significantly, very possibly eliminating the need for pesticides. This is your second or third release so far this year.
  • Remember that the population of natural predators and parasites always follows behind that of the pest. If predators are present in your garden, even in small numbers, they will need some time to catch up with the pest. Be patient.
  • Trichogramma wasps are very effective parasites of caterpillars. If these pests are usually a problem in your garden a couple of releases of these beneficials will be worthwhile. Space the releases 30 to 45 days apart.
  • Encourage larger beneficial wildlife in the garden as well. These include frogs, toads, lizards, many different birds and opossums.

Bulbs, rhizomes, tubers, etc:
(See also Bearded Iris, Dahlias, Cannas and Tuberous Begonias)

  • Bulbs that are in bloom in most parts of Orange County now include most alliums (late in the month), anemone, babiana, bletilla (just starting), calla, chasmanthe (finishing up), crocosmia (formerly called montbretia), daffodils, Dutch Iris, freesia, hippeastrum, hyacinth, iphieon (finishing up), ixia, narcissus, nectaroscordum, ornithogalum, ranunculus, scilla campanulata, sparaxis, sprekelia, tritonia, tulips and watsonia (just starting.
  • If you didn’t last month, plant or re-plant dahlia tubers now (see Dahlias).
  • This is the first opportunity to plant caladium. These need to be started when the soil is warm. Tuberose need even warmer soil, so wait at least another month for them.
  • Bedding cyclamen, although not generally referred to as a bulb, are still in full bloom, but are beginning to show signs of heat stress, especially in inland gardens.
  • As spring bulbs finish blooming do not hurry to cut back the foliage or ignore the plant. Keep the leaves in place and continue watering until the leaves naturally turn brown and dry, then you can cut them off. These leaves are sending energy to the bulb for next season. Of course, for one-year bulbs like most anemone, crocus, hyacinth, muscari, ranunculus and tulips, after they are done blooming, pull them and toss them. These will not return reliably next year.

California Native Plants:

  • Some of these will still be blooming and growing well, but many other will already be slowing down and preparing for the long, hot and dry summer months.
  • Be very cautious irrigating most of our native plants during the summer. Most of these are adapted to a winter wet – summer dry moisture cycle. Too frequent irrigations now (especially in soils with a clay content) will certainly cause problems.

Camellias:

  • Some Japanese Camellias may still be in full bloom. Be sure to keep the old flowers picked up underneath the plant to eliminate the occurrence of a disease called Camellia Petal Blight (a fungal disease that causes the petals to turn brown and mushy).
  • As soon as your camellia has finished blooming is the best time to do any shaping or other pruning to the plant.
  • Apply your first of three feedings to your camellia about 4-6 weeks after it finished blooming. Use an “azalea/camellia” or acid based fertilizer, like cottonseed meal. Apply a light application (camellias are not heavy feeders) evenly around the base of the plant, but do not dig it into the soil. Camellias (and many other plants) have very delicate surface roots within the top inch of soil that are easily damaged by cultivation. You will feed again 4-6 weeks later and then you final feeding 4-6 weeks later again.

Cannas:

  • They should be growing well this month, but probably won’t be blooming quite yet. Keep them fertilized with a general, well balanced organic fertilizer to help them along.

Citrus:

  • Citrus are growing pretty well this month and many varieties will still be flowering.
  • Continue fertilizing this month and every month from now until July. Use a fertilizer that is rich in such trace minerals as iron, zinc, manganese, copper and others. These ingredients are usually well represented in organic fertilizers like Dr. Earth.
  • Honeybees are the primary pollinators for citrus. Be sure to encourage these very beneficial insects and avoid any pesticides that might discourage or harm them.
  • Continue periodically checking for ants. Control them from climbing up the trunk of the tree or onto the branches. Although not directly harmful to the citrus, they are “farming” such pests as scale, whitefly and mealybug, which are all common on citrus.
  • Lemons and limes may have some ripe fruit this month. The first ripe kumquats are also appearing now. ‘Kinnow’ tangerines are about done and ‘Kara’ tangerines should be ripe pretty soon.

Clematis:

  • Clematis are continuing to grow well and quickly now. Keep feeding them with a balanced organic fertilizer to keep them going.
  • Most varieties will be blooming and those that are not should be heavily budded.
  • Help them as they grow by guiding their fragile stems or carefully tying to the arch, trellis or obelisk as they grow.

Dahlias (tuberous types):

  • Finish up planting (or re-planting) any dormant tubers. Choose a full sun location and drop a little fish bone meal or bone meal into each hole before planting.
  • For tall varieties, put stakes in now, to avoid damaging the roots later.
  • Keep newly planted tubers moist, but be careful not to overwater until growth shows above the soil.
  • When the foliage is a few inches out of the ground begin fertilizing. Use a liquid or granular organic fertilizer that is low in nitrogen and high in phosphorus. Fish Bone Meal is excellent.
  • When the stems are about eight or ten inches tall pinch off the top set of leaves. This will encourage the plant to branch and have more blooms.

Deciduous Fruit Trees:

  • Apply the second and final fertilizing this month. Apple, apricot, peach, plum, etc. should be given between about ½ pound of actual nitrogen per inch of trunk diameter. (Example: 15 pounds of 20% nitrogen if a six-inch trunk; 30 pounds of 10% nitrogen if a six-inch trunk, etc.)
  • Do the first thinning this month, the earlier the better. Twist off the excess fruit, leaving one per cluster and about one every six inches or so.

Ferns:

  • Some ferns, including sword ferns, chain ferns, some maidenhairs, etc., will begin waking up again this month, although most still need a bit more warmth.
  • When signs of new growth are showing, begin fertilizing. Use a mild, organic fertilizer on ferns and alternate periodically with an acid version, especially in high pH soil. For most common varieties try using blood meal alternated every third feeding with Cottonseed Meal.
  • As ferns begin growing new foliage consider removing old, dry or tired looking fronds all the way to their base. Some varieties like sword ferns, chain ferns, autumn ferns, rabbit-foot ferns and other rhizomatous varieties can be revived by cutting all of their fronds nearly to the soil. New growth will quickly reappear.
  • Begin irrigating more regularly according to weather and the growth of the individual plants.
  • Continue fertilizing mounted and containerized staghorn ferns with a mild, liquid fertilizer. Fish emulsion is excellent.
  • This is a good month to divide and/or remount overgrown staghorn ferns.

Fertilize:
(See also the information under the individual plants)

Fuchsias:

  • You should have stopped pinching at the end of last month. Now you want your plants to grow out and begin flowering. If you pinched and fertilized regularly over the past couple of months your plants will be very full and set loads of flowers.
  • Now that you are getting your plants ready to flower it is time to switch fertilizers. Put away the high nitrogen-high growth fertilizer that you were using and begin using a fertilizer that is more balanced or even slightly higher in phosphorus, to promote blooms.
  • Keep the plants well watered, especially during a warm spell.
  • Watch for Fuchsia Gall Mites, which are a serious pest of these plants. Look for any signs of puckered or distorted new growth. If you discover any, pinch it out and dispose of it immediately. A pesticide treatment is usually required.

Gardenias:

  • Gardenias are growing well now and may even be showing some blooms.
  • If you didn’t apply fertilizer last month be sure to this month. Use a fertilizer with lots of trace minerals, such as most organic types and alternate with an acidic formula to keep the pH down.
  • This is a great month to apply a good dose of an iron supplement to your plants. Iron only works well in warm soil temperature, so applying it now will have a significant benefit to the gardenias.

Geraniums:

  • This group includes Ivy geraniums, Zonal geraniums (also called “Common” geraniums), Martha geraniums and the various scented geraniums, but does not include true geraniums (sometimes called “Hardy” geraniums), which are discussed under Perennials.
  • Ivy and Zonal types should be blooming well now. Remove spent flowers to the bottom of the stem regularly to encourage more blooms.
  • Fertilize all geraniums, except most scented types, regularly with a balanced fertilizer. Geraniums prefer a slightly acidic soil, so periodically alternate feedings with an acid fertilizer, such as Cottonseed Meal.
  • Ivy and Zonal geraniums do not like heavy pruning. To keep the plants shapely and vigorous for a longer period of time prune back a few long stems every month or so from now through fall, but never very many at one time.
  • Stop pinching Martha types (but keep feeding) and allow them to go into full bloom. Remove spent flower clusters regularly just below the flower to encourage more blooms.
  • This is the month that budworms usually begin attacking. They primarily feed on the developing buds, but also feed on new leaves as well. If necessary, spray with BT on a regular basis beginning now.
  • Rust may appear about now, especially on Zonal and Martha varieties. First seen as small brown clustered and raised spots on the undersides of the foliage this is nearly impossible to control chemically. However, it is generally a short term springtime issue and can be managed through proper culture. Fresh air circulation, adequate sunlight and keeping the foliage dry in the evening are suggested.
  • This is still a good time to take healthy three to four inch tip cuttings to propagate all varieties. For best results use sterile shears, let the cutting “cure” for a few hours in a dry shady area and root them in clean potting soil and clean pots. When thoroughly rooted plant them into the garden to replace old, tired and woody plants.

Grapes:

  • Grapes should be growing vigorously now. Direct the canes as desired.
  • The first application of fertilizer should be made when the new growth has grown a couple of inches (probably last month). Assuming the use of a granular organic product, the second application should be six to eight weeks later, the third application another six to eight weeks later and the final application in another six to eight weeks.. Remember, use a well-balanced product that contains trace minerals, which grapes need. Organic products usually are a good choice.

Groundcovers:

  • This and last month are the best time to plant slopes, especially large scale plantings. Erosion will be minimized since most of the rains are behind us.
  • Cool season groundcovers are still growing and blooming well, enjoy the show.
  • California native groundcover plants, like Ceanothus and Arctostaphyllos (Manzanita) are probably still blooming well now. This is not a good month to plant these. Wait until late this fall.
  • Warm season groundcovers are waking up and growing again, possibly even setting flower buds. Feed these now with a balanced, organic granular fertilizer.
  • If necessary, this is the best time of the year to perform a heavy cutting-back of warm-season varieties. Many groundcovers build up considerable thatch and loose their vigor if not cut back periodically. In general, the faster they grow the more frequently they need a firm cutting back. Fertilize after the cut-back, to insure quick recovery.
  • Groundcover planting in general is easy to accomplish now. Mulch between the plants after the planting to reduce weed growth, improve soil quality and reduce irrigations.
  • This is another good time to check irrigation systems on slopes. Adjust heads, check clogged lines and add to the system as necessary, before the warm weather of summer.

Herbs:

  • Now that the weather is warm and the days are growing longer is the best time to plant basil.
  • Many perennial herbs can be planted nearly year-round, but are particularly well suited to spring planting, since they thrive during the warm summer months. These include marjoram, oregano, rosemary, sage, thyme, catmint, catnip, chamomile, comfrey, feverfew, lavender, lemon balm, lemon grass, lemon verbena, St. johns wort, tansy, tarragon and thyme.
  • Especially in warm inland gardens, this is the last chance to plant a quick crop of fast growing, cool-season herbs like anise, arugula, borage, chervil, cilantro, dill and fennel.
  • Annual “summer savory” can now be planted in the warmer weather. The perennial “winter savory” can also be planted now, however the flavor of the perennial version is generally considered inferior.
  • This is still a good time to rejuvenate certain old or tired herbs by giving them a hard trim. These include chamomile, chives, garlic chives, lemon balm, lemon grass, marjoram, mint, oregano, salad burnet, sorrel, St. johns wort, thyme and watercress. All of these can be scalped almost to the soil line and, with fertilizing, will recover quickly. Other herbs like catmint, catnip, feverfew, lemon verbena, rosemary, rue, sage and tansy should be cut a bit higher. Cut lavender only very lightly.

Hydrangeas:

  • These are continuing to wake up from the cool winter months and should be putting on nice new growth. They are growing nicely and a few may even be beginning to bloom.
  • Apply a moderate feeding.
  • Do not prune hydrangeas at all this time of the year. Hydrangeas bloom on one-year-old stems. Pruning now will eliminate most of the flowers.
  • If you want to try to get blue or lavender flowers on your otherwise pink plant you need to continue applying Aluminum Sulfate to the soil. White flowered varieties will not be effected and not all pinks will be effected the same.

Lawns:

  • This is a good month to plant new cool-season lawns from seed or sod (fescue, ryegrass, bluegrass).
  • Feed all lawns this month. Cool-season grasses like fescue, ryegrass and bluegrass are still at their peak in the cool springtime weather. Warm-season grasses like bermudagrass, St. Augustine and zoysia have waken up and are growing well again. Feeding these warm-season grasses now will help them return to their deep green color.
  • This is the last really good month, until fall, to plant new cool-season lawns (fescue, ryegrass, bluegrass).
  • Conversely, it is the first reliable month to plant warm-season lawns (hybrid bermudagrass, St. Augustine, etc.) from sod. Most warm-season grasses do not grow from seed and are best only installed from sod.
  • Remember, cool-season lawns should be mowed about a half an inch lower in the cool months than in the warm months. Keep the mower at this lower height for another month or so.

Orchids (outside grown):

  • Most cymbidiums are wrapping up their bloom cycle this month. Continue feeding with a high phosphorus fertilizer through the end of their bloom period.
  • After your cymbidium has finished blooming
  • As epidendrum orchid flowers fade, cut the individual stems to two or thee buds above the soil. This will keep them blooming almost year-round.
  • Keep feeding epidendrums with a low nitrogen/high phosphorus fertilizer.

Ornamental Grasses:

  • The ornamental grasses that were cut to the ground sometime during the winter have now put on a lot of new growth.
  • This a very good time to plant nearly any species of ornamental grass.

Perennials:
(See also Bearded Iris, Bulbs/Rhizomes/Tubers, Cannas, Dahlias, Fuchsias, Geraniums, Ornamental Grasses and Tuberous Begonias)

  • There is a myriad of new and interesting plants at nurseries this month. A slow walk through the nursery now will stimulate lots of exciting plant possibilities.
  • This is a good planting month for perennials. The selection is good and many will be in bud or bloom.
  • Keep fertilizing your perennials. The frequency and amount will depend upon the formulation that you are using. If you have been building up your soil health your fertilizing duties will be much reduced.
  • See separate entries for bearded iris, bulbs/rhizomes/tubers, cannas, fuchsia and ornamental grasses.
  • Most of your perennial “chores” should have already been done and you can now enjoy your perennials in all their colorful glory.
  • Sub-tropical perennial are beginning to perk up now. This is also a good month to plant these. These include begonias, heliotrope, impatiens, lamium, pentas (starflower) and plectranthus.
  • By now most of the perennials that completely withdrew to below ground for the cool winter months have sprouting from the soil again. Some of the last perennials to sprout that you should still be on the lookout for include caladium, calla (colored types), chocolate cosmos and some true lilies (lilium).
  • Tall, upright, spiking perennials like dahlia (tuberous perennial types), delphinium, foxglove (digitalis), kniphofia (red hot poker), liatris, true lilies (lilium), monkshood (aconitum), oriental poppy and most thalictrum (meadow rue) should have stakes in place to support the flower stalks and prevent breaking. Tie the stalks to the stakes as they grow.
  • Removing the myriad of spent or old flowers regularly always helps them to produce more new flowers. This is a good time to cut some fresh flowers for a vase as well.

Pests & Diseases:
(See also the information under the individual plants and Beneficial Insects)

  • Snails and slugs . . .
  • Aphids
  • Release beneficial insects.
  • Watch for caterpillars. Spray with BT if necessary.
  • Fuchsias gall mites.
  • Look for Giant Whitefly and control it now.
  • Eugenia psyllid.
  • Plant plants that attract beneficial insects and pollinators.
  • Rose slug.

Huntington Library

Places to Visit:

  • Gardens that look terrific almost any time of the year include Sherman Library and Gardens (Corona del Mar), The Fullerton Arboretum (Fullerton), Los Angeles Arboretum (Arcadia), Huntington Library and Botanical Gardens (San Marino) and Quail Botanical Gardens (Encinitas).
  • Rancho Santa Ana Botanic Garden, Clairemont. Hurry.
  • Niguel Botanical Reserve, Laguna Niguel.
  • Rose Hills Memorial Park.
  • During the first half of the month is the big Southern California Spring Garden Show at South Coast Plaza. Over 75,000 people attend this indoor show with over 100 garden vendors, garden experts and displays. Free.
  • Home garden tours.
  • Richard Nixon Library and Birthplace, Yorba Linda.
  • The “Green Scene” at The Fullerton Arboretum is one of the best garden events in southern California, and it’s right in our own backyard. Usually held the last weekend of April, this outdoor event features well over 100 plant and garden exhibitors, hard-to-find plants, garden seminars and more.
  • This is a good time for a visit to our canyons and chaparral areas to observe our native plants. Good choices might include Black Star Canyon, Trabuco Canyon and the upper San Mateo Creek area.

Planting:
(See also the information under the individual plants)

  • Trees, shrubs, perennials, flowers, vegetables.
  • This is another good month to plant warm-season flowers from color pacs or small pots. Good choices for putting in the ground now are marigolds, lobelia, petunia, ageratum, alyssum, cosmos, verbena, coleus, begonias and impatiens. It is still a month or two too early for the super heat lovers like zinnia, portulaca, vinca, and lisianthus (eustoma).
  • Cool-season flowers like primrose, pansies, violas, Iceland poppies, bedding cyclamen, stock and snapdragons are still going strong. Keep these fertilized and deadheaded.

Poinsettias:

  • Potted holiday poinsettias should be outdoors by now. They may be looking pretty rough now.
  • If you didn’t last month, cut the tops off to two or three buds near the base (probably about 3-4 inches high).
  • Gradually transition to plant to a full sun location.
  • Begin fertilizing the plant with a well balanced food and new growth will begin sprouting from the dormant buds at the base of the plant.

Records, Catalogs, Books and Organizations:

  • Be sure to continue to make lots of entries in your garden journal now about what is blooming, what you like and what you don’t. Especially important are entries that you will make now that guide you and remind you of what you should do this fall.
  • With even more planting this month be sure to make some notes in your journal about the names and varieties of what you planted. Often, much later, the name or variety of a plant cannot be remembered. After the plant is taken out of the can save the tag and jot a note into your journal about where and when you planted it.
  • Make notes now in your garden journal about which roses are performing well and which are not. Notes on disease tolerance will be useful next winter if you decide to switch to some improved varieties.
  • This is the biggest month for home garden tours. If you haven’t participated in one of these before you have missed one of the most rewarding gardening experiences.

Roses:

  • Roses are making their first big bloom this month. This “first bloom” is the most spectacular of the entire year. The flowers will be huge and the color rich. The flowers will hold well in the cooler temperatures of April and the foliage should be lush and healthy as well. Enjoy the show.
  • Continue fertilizing roses. They are heavy feeders. Do not use soil-applied fertilizers that are combined with a systemic insecticide. These products are very disruptive to soil life (beneficial microorganisms, bacteria, mycorrhizal fungi, earthworms, etc.). Many rosarians also believe they reduce the vigor of the rose.
  • Granular, well-balanced, organic fertilizers work especially well for roses and most of these will encourage beneficial soil life.
  • Begin deadheading roses as they fade. The rule of thumb is to prune to just above a leaf with five leaflets. Floribunda’s, many English roses and some others are deadheaded on very short stems until the last of the flowers in the cluster have faded. Then cut down to just above the first leaf with five leaflets.
  • Be on the lookout for pests. Aphids can usually b hosed off with a strong jet of water. Flower thrips may require an insecticide.
  • Keep on the lookout for diseases. Powdery mildew and rust are the primary concerns. Regular grooming, early removal of infested leaves, good air circulation and full sun will help considerably.
  • If diseases do require a fungicide, use one of the newer, safer, organic products available. These include Rose Defense (a neem oil extract), E-Rase (jojoba oil) or Saf-T-Cide (straight paraffinic oil).
  • Potted roses are in good supply and the selection is excellent now at the nursery. It is a good time to add more or upgrade any that you are struggling with.
  • Make notes now in your garden journal about which roses are performing well and which are now. Notes on disease tolerance will be useful later if you decide to switch to improved varieties.
  • One of the most obvious pests, especially in coastal gardens is now beginning to show up. Commonly called “Rose slug”, it is not a slug at all, but the larval form of a fly relative, called a Sawfly. These tiny little caterpillar-like pests are hard to spot, but feed by chewing on the undersides of foliage. Eventually, irregular holes are eaten through the leaves. Neem oil will work on them as will organic Pyrethrin sprays, but the application must be thorough and applied to the undersides of the foliage.
  • Irrigations will be more frequent now as the weather warms and the days lengthen.
  • For the biggest flowers pinch out some of the competing buds while they are very small.
  • Weed as needed, but avoid most herbicides around roses.

Shrubs & Vines:
(See also the information under Azaleas, Camellias, Gardenias, Hydrangeas and others)

  • In general, many shrubs will be growing rather quickly now and they may want to grow too large for their space. They may even want to grow into small trees. This may be what you want, but if not they will need regular clipping to restrain them. Pruning these shrubs is best done just following their bloom cycle so as not to interrupt their flowering. For many shrubs this may be now.
  • This is about the time to prune winter and spring flowering vines that have finished blooming. These include Pink Jasmine (Jasminum polyanthemum), Hardenbergia species (Lilac Vine), Jessamine (Gelsimium species), Cat’s Claw (Macfadyena unguis-cati), Flame Vine (Pyrostegia venusta) and Wisteria (see separate entry).

Soil Care:

  • We have included this section, because as you know, or will discover with more experience, a good garden begins with the soil. Investing in the soil, managing the soil and protecting the soil are not afterthoughts in a successful garden, but the foundation. Healthy soil is living and breathing, teaming with earthworms, microorganisms, beneficial fungi, bacteria, microbes and other invisible life. This section, possibly the most important topic of all will, provides some helpful guidance to good soil care.
  • A thick layer of organic mulch, averaging about two inches should be maintained on top of the soil just about year-round. This is possibly the best month of the year to add additional mulch as needed to maintain this level.
  • Applied now, a thick layer of mulch will cool the root systems from the hot temperatures ahead, reduce irrigations as much as half during the summer, reduce weed growth, and improve both soil life and soil quality.
  • If you have been considering inoculating your soil with beneficial mycorrhizae, this is a perfect month in which to do it. The soil temperatures are just right for quick establishment. This can be done quickly and easily in established areas by using mycorrhizae “tablets”. In moist soil, poke a hole near the plant with a ½” or ¾” rod or stick. Drop a tablet into the hole and push it in again with the stick.
  • We do not suggest the use of very high analysis fertilizers in a garden, especially phosphorus. Examples of fertilizers to avoid are synthetic versions with formulations like, 10-55-10, 10-30-10, etc. We don’t even suggest the popular 15-30-15 formula. These formulations will inhibit or even destroy much of the soil life that is so vital to a healthy sustainable soil.
  • We also suggest that you not use soil-applied systemic fertilizer/insecticide combinations (especially popular with roses). These are very damaging to soil life.
  • Use insecticides only when necessary and even then use the least damaging product available. Many of these products move into the soil and interfere with the invisible soil life.
  • If you can, begin a compost pile or purchase a compost bin. Leaves, clippings, kitchen produce scraps, and many other ingredients can be composted and returned to the garden. Home compost is one of the very best ingredients you can add to your soil. The benefits are huge in the areas of disease suppression, increasing beneficial microorganisms, improving soil structure and texture, nutrient retention and nematode suppression.
  • This is definitely a planting month. Be sure that before you plant you have considered the soil and are doing all you can to improve it and protect its health.
  • If your soil PH is too high (alkaline) this is one of the better months of the year to lower it. Two methods are both effective. Using a low PH mulch over the surface is probably the most effective. The other is with the incorporation of soil sulfur, an organic naturally occurring acidifying chemical.

 

Strawberries:

  • Feed them regularly. Periodically alternate with an organic acid fertilizer, like cottonseed meal, to keep the soil pH low, which strawberries prefer.
  • Bait, trap or hand pick snails and slugs regularly to avoid fruit damage.
  • Strawberry fruit is less likely to be bothered by sowbugs, earwigs or rotting if separated not in contact with the soil. Straw works well for this as does pine needles or even rings cut out of unprinted corrugated cardboard. All of these can be turned into the soil at the end of the season.

Subtropical Fruits:
(See also the information under Avocados, and Citrus)

  • Annual pruning, if needed, can often be done now, but consult a reference or expert first. Some varieties only bloom and set fruit on old wood and pruning now would be incorrect for these.
  • Most of these are still just waking from the cool months. Some varieties will be showing signs of new growth on the tips or along the branches.
  • Depending upon your location and the species involved, you may be able to begin planting.
  • Most varieties can be fertilized now, but wait another month on any that look completely asleep.
  • Watering can usually be more frequent now, as the plants wake and begin growing again.

Sweet Pea – Harbinger

Sweet Peas:

  • These should still be in full bloom about now. Keep the flowers trimmed regularly to encourage more flowers. This may be as often as twice a week. Sweet peas are one of the plants that really benefit from having their flowers trimmed.
  • Feed regularly.
  • Assist them with climbing and support if necessary.

Trees:
(See also the information under Avocados, Citrus, Deciduous Fruit Trees and Subtropical Fruits)

  • This is a good month to prune tender sub-tropical trees like Ficus, Coral Tree, Avocado, Citrus, etc.). These sub-tropical trees should not be pruned during the cool winter months. However, care must be taken not to disturb nesting birds at this season.
  • Many trees may be suckering heavily now. Remove these suckers below ground by pulling them. If you cannot pull them, dig them to the point where they are attached to the tree and cut them flush with the root or trunk, leaving no “stub”.
  • This is a very good time to plant most tender, subtropical trees like coral tree (Erythrina), orchid tree (Bauhinia), trumpet tree (Tabebuia) and others.

Tropicals & Subtropicals:
(See also the information under Avocados, Citrus and Subtropical Fruits)

  • Most of these are still just waking from the cool months. It is still early for most of these plants. Some varieties will be showing signs of new growth on the tips or along the branches.
  • Depending upon your location and the species involved, you may be able to begin some plantings.
  • Most varieties can be fertilized now, but any that look completely asleep still should wait another month. Don’t be surprised if the real heat lovers, like Plumeria, Ginger, Ixora, Heliconia still have no sign of new growth.
  • This is a good month to do any serious hibiscus pruning.
  • Watering can usually be more frequent now, as the plants wake and begin growing again.

Tuberous Begonias:

  • Tubers should be sprouting in the flats that you put then into last month.
  • When there is about two to three inches of growth on each tuber gently scoop it out of the stay with a spade and a bit of soil under it. Place it into a basket, pot or well drained bedding area where it will grow and bloom for the rest of the summer and into the fall.
  • Begin fertilizing. Tuberous begonias are heavy feeders, especially in containers. Use a well balanced fertilizer and periodically mix in an acid fertilizer, since these prefer a low soil pH.
  • Keep them well watered, but not soggy. The soil should be rich and well-drained. The surface of the soil should dry slightly between watering.

Vegetables:

  • There is still time to plant artichokes from gallon containers and get fruit this year. If your artichoke is re-growing from last year or was planted earlier this year remove any suckers on the plant. A single crown will produce larger fruit. The suckers can be given away to friends or re-planted elsewhere in the garden.
  • Early this month may be the absolute best time to plant tomatoes from transplants. A crop planted now will produce for several months. Choose varieties carefully; hundreds are available.
  • Mound spring potatoes that you planted last month.
  • Putting in successive plantings of many vegetables a couple of weeks apart from each other will insure a constant, uninterrupted supply for the kitchen.
  • Early potatoes from those planted last fall may be ready for harvest.
  • In a well established asparagus patch, this is still a good time to harvest asparagus spears. Remember, don’t take any spears during the first two years after planting.
  • Almost any warm-season vegetable can be planted this month. From transplants or seeds, plant beans, celery, cucumbers, eggplants, okra, peppers, salsify, squash, sunflower and tomatoes. Corn, lima beans, jicama, melons and pumpkin are best planted from seed.
  • Along the immediate coast most cool-season crops like arugula, lettuce, peas and members of the cabbage family can still be grown. Alternatively, the real heat-loving vegetables like corn, melons, peppers and pumpkins will be challenging. Grow them in front of a hot south facing wall.
  • Plant corn from seed this month. Because corn needs to be cross-pollinated it must always be grown in clumps or rows. Twelve plants is about the minimum for good pollination and twenty or more is even better. Plants crops successively every three to four weeks for a continual harvest.
  • Beets, carrots, chard, radish and possibly turnips can be planted just about year-round. All but chard are planted from seed only.
  • Since most annual vegetables are shallow rooted and quick growing, feed them regularly with a well balanced organic fertilizer
  • Control weeds before they get out of hand.

Water & Irrigation:
(See also the information under the individual plants)

  • Automatic timers might be turned back on now if the weather warrants.
  • Adjusting the duration and interval settings of automatic sprinkler systems as the weather dictates.

Wildflowers:

  • Most of these will be over their bloom peak and beginning to look a little stressed. You may be able to extend their season a bit with some additional irrigations.
  • If you want some of your wildflowers to re-seed for next year, leave them in place for a while and allow the seed to fall to the soil.

Wisterias:

  • This is the main month of bloom for wisterias. If proper pruning was followed all year, established plants should be in full, glorious bloom now. Enjoy.
  • No pruning now or you may interfere with the blooms.
  • Select and plant new wisterias now, while they are in bloom. Grafted plants are preferred, since they will almost always bloom at a much younger age.
  • There is still no need to fertilize now and irrigation is only needed on young, newly installed plants.
By | 2017-09-28T14:54:03+00:00 April 5th, 2017|Gardening, Gardening Checklist|4 Comments

About the Author:

4 Comments

  1. hcl tank May 19, 2013 at 5:27 am - Reply

    This is very fascinating, You’re an overly professional blogger. I have joined your rss feed and look ahead to looking for more of your magnificent post. Additionally, I’ve shared your website in my social networks

  2. Leslie April 3, 2015 at 6:43 am - Reply

    I bought a young avocado tree from Roger’s last year. It went into shock after planting so it did not bear fruit. I was so disappointed when the blossoms fell off this spring though the tree looked healthy. I contacted Eric at UCR (Eric Focht ) and he gave me this helpful information which you might want to pass on to your readers:
    . . . avocado trees typically have literally millions of flowers of which, only several hundred will make it to fully mature fruit in a fully grown tree.

    As long as your tree is growing healthily, you’ll be fine if you just wait. A planted tree usually comes into full maturity 5-10 years after planting

    • Roger's Gardens April 3, 2015 at 11:47 am - Reply

      Glad your tree recovered Leslie. Eric’s answers are spot on. Avocados are notoriously unpredictable about their bearing age. Ten trees, all bought and planted on the same day at the same location, will each come into production at different times, and there is not any way to predict that and adjust that period. Don’t be surprised either if at some point you see little pea to ping-pong ball sized avocados developing and then dropping. This is normal and is a results of incomplete pollination or the tree’s natural fruit thinning.

      Glad you got some great advice.

      Ron

      • Leslie April 10, 2016 at 8:24 am - Reply

        Here I am, 2 years after planting my avocado tree, and still no fruit. As your blog says, most of the leaves shed but that was followed by lots of blossoms and healthy leaf growth. I had no idea that growing avocados was for patient people. The little Charlie Brown looking Gold Kist apricot tree that I purchased at Roger’s last summer is bearing 2 fruit. Nothing to brag about, but satisfying for it’s first year.

Leave A Comment