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To-Do List - May
by Karen Bodner, MG
Sow indoors: In addition to those veggies mentioned last month, you can add cucumbers and long-season Brussels sprouts (transplant June 1) to your list. Later in the month sow squash in four-inch pots and corn. Keep the latter in pots no more than two weeks, and, if sown in peat pots, tear the lip off to below soil level to prevent a water-wicking effect. I had great success in fifty-cell trays transplanted at exactly two weeks into black plastic mulch, so I'm still hoping for Fourth of July corn in my pot.
One handy trick for sowing corn is to place clear plastic over the area to warm soil two weeks before sowing. After sowing, replace plastic until germination; this technique can easily give you a ten-day earlier start.
Continue to harden off and transplant seed started earlier and cover with Reemay, open-ended plastic, or slit plastic. Reemay can be left in place regardless of temps, and plants under slit plastic can endure much more heat before opening than ones under regular clear plastic. They grow significantly faster protected this way.
Squash and beans can be sown in greenhouses early in the month. And, believe it or not, the end of the month is also time to sow late and autumn cabbage and cauliflower indoors!
Sow directly in garden: kale, endive, radicchio, parsnips, carrots, early cabbage, lettuce, onions, peas (inoculate and use enation-resistant varieties now), short-season Brussels sprouts, broccoli, beets, radishes, spinach, kohlrabi, tomatoes and peppers (asap or buy starts). In the second half of month sow beans, okra, squash, pumpkins, and Chinese cabbage.
Covering smaller or shallowly planted seed with a thin layer of vermiculite will help retain moisture and help prevent soil from drying out during germination. Beans and squash prefer a drier germination. Sow deeply (11/2 to 2 inches), water at planting, and avoid watering again until sprouted. If sowing inside, squash should be sown in four-inch pots and transplanted in no later than three weeks for best results.
Any tomato or pepper plants put into the garden should receive good protection (Wall o' Water or plastic cloche). Plant seed potatoes later in month if weather is still mild.
Flowers, herbs, and bulbs
If purchasing chrysanthemums now for fall color, pinch tips occasionally to keep bushy and compact until six weeks before desired bloom. Continue to direct sow hardy annuals, perennials, herbs (won't bloom this year unless chilled), ornamental grasses, marigolds, petunias, nasturtiums, impatiens, and sunflowers (second half).
Also fertilize lilacs, begonias, and fuchsias. Plant gladiolas, dahlias, and other hardy and tender bulbs. Monitor plants for disease and insects. Work one to two inches of well-composted manure or compost into flower beds two to three weeks before planting. Overgrown, vigorous rosemary plants can be renovated at this time by cutting all stems back by at least half. Continue to plant bulbs for extended blooming season.
Vegetative propagation: Take basal cuttings from asters, Centaurea, Campanula, Chrysanthemum, Diascia, Erigeron, Humulus, and Lavandulai Linaria to name a few.
Fruits and nuts
Be sure to water new plantings deeply. Spray cherries this month for brown rot blossom blight. Check your spray schedule for other applications. Routine strolls around your trees will ensure that signs of disease and insects will be detected early.
Trees and shrubs
Fertilize roses early this month; check for mildew and black spot. Continue to plant new trees and shrubs; keep well-watered. Fertilize rhodies and azaleas, and prune after flowering if leggy or otherwise necessary; deadhead. If it's necessary to prune your rhody, look for small growth bumps down on the trunk and cut to just above them. If it doesn't have these bumps, it may not respond well to hard pruning.
Prune and fertilize spring flowering shrubs and trees after flowering to allow energy to go into next year's growth and buds. Fertilize fuchsias and begonias.
Vegetative propagation: Take tip cuttings from Acer, Abutilon, Clematis, Cotinus, Fuchsia.
When the soil is dry enough, use a motorized or hand-powered tiller to break ground, working in fertilizer and amendments. Work in overwintered cover crops two to three weeks before planting. Thatch and aerate lawn this month if necessary. Get irrigation equipment organized and set up before you really need it.
Slugs are the first, and only, bad guys I've seen so far. I've delighted in seeing rove beetles, ground beetles, and numerous bees and wasps. Thousands of tadpoles crowd the bottom of the pond, although I hear the parent frogs down the road in another yard. I'm wondering if I did something to offend them! The critters will really be on the move now, so know who eats what (or whom), and keep your eyes open.
Get close to your plants; turn leaves over. Nighttime forays into the garden are rewarded by rove and ground beetles and an occasional tree frog hopping by. Since slugs are taking a short break from egg-laying, any "garden pickles" you get now will be 400 eggs less (at a time) later!
Vegetable plantings of cabbage, cauliflower, onions, radishes, lettuce, etc. can be protected from pests by using floating row covers. Codling moth and cherry fruit fly are expected this month, so set traps to determine their presence and your spray schedule. Also, our Extension Service always puts out a press release when they appear.
Check your currants and gooseberries for eggs from the currant fruit fly and for symptoms of currant aphids, which are indicated by red mottling on some of the leaves. Treat with pyrethrum or insecticidal soap. Check your strawberries and other ornamentals for aphids and spittle bugs because our lists are approximate in time frame. Depending upon location and weather, pests may show up earlier or later. Here is a list of who is springing into action this month:
A =Adult E =Egg, P =Pupa, L =Larva, N =Nymph and beneficials are italicized
western damsel bug-A
minute pirate bug-A
alfalfa leafcutting bee-P
carrot rust fly-A/E/L
green peach aphid-A/N
western cherry fruit fly-A/P
peach twig borer-A/P
cabbage flea beetle-A/E
elm leaf beetle-A/E/L
bark beetle-A/E/L (flight early May)
white grub beetles-A/L/P
bean and currant aphids-A/N
western flower thrips-A/E/N
raspberry crown borer-L
holly and soft scale-A/E
strawberry crown moth-P/E
western raspberry fruitworm-A/E/L/P
San Jose scale-A/N
oyster shell scale-N
slugs-A & young
walnut husk fly-P
box elder bug-A/E/N
seed corn maggot-A/E/L