We’ve had a wonderful spring this year. Whatever May brings, let’s remember that we have been gifted with cool days and nights, a few late storms that brought snow and some rain, and an abundance of flowers and other signs of vigorous life in our gardens. I’ve been working on photographing pollinating insects this spring, and it’s given me a real appreciation for the diversity and industry of these garden allies, many of them tiny and easy to overlook, not all of them beautiful or glamorous. But amazing as part of the balance that keeps everything healthy without many pesticides or added fertilizers.
PLANTING: With the recent rains, we can continue to plant into May. Try to finish planting in the ornamental garden before summer weather arrives. You can plant water-loving plants through summer, but even for them, transplant shock will be lessened if you can plant while we still have cool nights. Almost everything can be planted now, especially early in the month. Bulbs, tubers, and corms to plant are dahlia, gladiolus, and tuberose. Succulents are fine to plant now too, as are avocados, citrus, bougainvillea, and other frost sensitive plants. Summer color can liven up both the ornamental and edible gardens. Species to plant now include zinnia, marigold, petunia, sunflower, cosmos, and impatiens.
Vegetables to plant now include tomatoes, peppers, basil, eggplant, summer squash and tomatillos. Don’t worry about some shade in your edible garden. Many summer garden vegetables do fine if they get at least six hours of sun a day, which is just about half a day. Heat lovers to plant in the full 14 hours of sun we can expect are winter squash, melon, okra, beans, and corn. Why not try a three-sisters garden of corn, beans, and squash? If you have an established garden, care for your soil by adding straw, compost, and composted manure or, if you must, store-purchased amendment. If your soil is healthy, your plants will need far less pest and disease management, making the garden healthier and less work.
MAINTAINING: Check your watering system and adjust as the weather warms. Your new transplants will need to be supplied with water on a regular basis through late spring and right into summer. Don’t expect even low-water-use plants to survive on no water during their first year. Deep water stone fruit, apple, pear, and nut trees. For established gardens, the top several inches of soil can dry out for almost all plants in the well-mulched garden and in whatever lawn you still have. Many people over water their lawns, especially in late spring. This encourages disease and insect problems.
Prune spring-blooming shrubs like camellia, lilac, and hydrangea as they finish flowering. Pinch back fall-blooming chrysanthemums until July. Deadhead roses (remove old flowers) to encourage repeat blooming. Trim off suckers from the base of roses and from trees and take out any dead branches now that trees are fully leafed out. If you haven’t already, thin your nut and stone-fruit trees when the fruit are small to improve fruit size and quality. How much will you realistically consume? Thin, and then wait a day or two and then thin some more. Branches may break if they are overloaded with fruit. For young trees, less than five years old, allow only a few fruits to grow to maturity so the tree can put more energy in root and shoot growth. Cage young trees with field fence or rabbit wire and sturdy posts to prevent damage from ground squirrels, rabbits and deer in the foothills and mountains. Sometimes you need to cage below as well to prevent damage from gophers and ground squirrels.
Continue with weeding. Add compost and/or mulch if you haven’t already to your planting beds. Keep wood mulch at least six inches away from tree trunks. Raise the mowing height to three inches for all types of lawn to shade out weeds and keep roots cooler.
Monitor the edible garden for common warm season insect pests: earwigs, aphids, slugs, snails, and grasshoppers. Blast soft-bodied insects like aphids with a stream of water. Insecticidal soap is a good all-purpose insecticide for many insects, and it doesn’t kill as many beneficial insects as broad-spectrum powders and sprays do. Try to tolerate some damage, to feed garden friends like birds, spiders, lacewings, ladybugs, assassin bugs, lizards and praying mantis. Hand pick tomato/tobacco worms, hoplia beetles on roses, snails, and slugs. Leave rolled newspaper traps or put a little oil into opaque bottles and leave them laying sideways under garden plants to trap earwigs. The traps need to be put in the waste every morning until the population is diminished. Control scale (they appear as little bumps on stems of citrus, bay, and other plants) with summer horticultural oil. You may need to repeat application in June. Follow package instructions to avoid harming your plants.
Fertilize your container plants now. Once a year is usually enough for most containers. Once every three years may be all that is needed for California native plants in containers. You may never need to fertilize your succulent and cactus. Fertilize azaleas, camellias, and gardenias with fertilizer labeled for them. Fertilize citrus with fertilizer labeled for them. Citrus in containers need to be fertilized at least once a month during their blooming and growing season. They’ll live without it, but may not produce much, if any, fruit. Citrus in the ground should be fertilized this month and then not again until next year. Fertilize your warm-season lawn and groundcovers with an all-purpose product to promote vigorous growth and help prevent weeds. If you haven’t already, fertilize your roses. You may find that compost is all you need; don’t feel pressured to add store-purchased fertilizer if your plants are vigorous and healthy. Sometimes we think we “must” do things, but do we need more growth that we will need to prune later? Do we need more fruit that will just end up on the ground or compost bin? Many low-water-use plants are better off without fertilizer to keep them longer-living and more compact.
CONSERVING: Don’t disturb your bee nesting and bird houses. Observe your trees before having the tree trimmers come to make sure you’re not disturbing an active bird nest. Leave a little radish, mustard and broccoli blooming in the edible garden until seed set to support pollinator insects. Consider adding a new plant for the wildlife. Do you have room for a quail bush (Atriplex lentiformis), mulefat (Baccharis salicifolia) or California fuscia (Epilobium californica)? Do you have room for yarrow, California buckwheat or CA native milkweed? Native milkweed has pink and white, not yellow or orange, flowers. Can you dedicate a space in the garden that is less manicured? This will support the greatest diversity and number of native bees, beneficial insects, lizards, toads, and birds. And that is what makes a beautiful garden.