Edibles: Fruits
ALL WEEKS
-Mulch blueberries with pine needles or sawdust.
WEEK 1
- Orange, jelly-like galls on cedar trees spread rust diseases to apples, crabapples and hawthorns.
- Begin sprays for fire-blight susceptible apples and pears using an agricultural streptomycin.
WEEK 2
- Spider mites and codling moths become active on apples.
- Prune peaches and nectarines as soon as buds start to develop. Do not prune "pit" fruits in winter, when they are dormant.
WEEK 3
-Don't spray any fruits while in bloom. Refer to local Extension publications for fruit spray schedule.
-Mulch established raspberry canes with well-rotted manure or compost to keep the soil moist, cool and nourished. Also, mulch blackcurrant bushes, but first ensure the soil is moist.
Edibles: Vegetables
ALL WEEKS
-Be careful when bringing home vegetable and herb seedlings. If grown in a greenhouse they are very susceptible to sunburn and wind whipping. Acclimate plants gradually to outdoor conditions to avoid setting them back or damaging tender new growth.
-Place cutworm collars around young transplants. Collars are easily made from cardboard strips.
-Growing lettuce under screening materials will slow bolting and extend harvests into hot weather.
-Slugs will hide during the daytime beneath a board placed over damp ground. Check each morning and destroy any slugs that have gathered on the underside of the board.
-Deter flea beetles by sowing a thin line of mustard seed around the seedbed where cabbages and other brassica plants are being raised.
-Don't kill centipedes. Unlike millipedes, which chew plants, centipedes eat insect pest such as grubs, slugs and woodlice. Centipedes have one pair of legs on each body segment, whereas millipedes have two and are slow-moving.
-Earthworms are essential to gardens, so do not kill them. They help aerate soil, improve drainage and assist in mixing dead plant and animal remains in the soil.
WEEKS 1 & 2
- Begin planting lima beans, cucumbers, melons, okra and watermelons.
- Begin setting out transplants of tomatoes, eggplants, peppers and sweet potatoes.
WEEK 1
- Prepare new asparagus beds- dig trenches 15 inches wide and 12 inches deep.
- Sow scallions ½ inch deep in drills 5-6 inches apart.
- Sow garden peas 4 inches apart in drills 2 inches deep, and summer spinach 1/2-1 inch deep in drills 12 inches apart.
WEEK 2
-Sow radishes ½ inch deep in rows 8-12 inches apart.
-Sow maincrop potatoes 6 inches deep and 15 inches apart in rows 2 ½ feet apart. This ensures that there is plenty of room for their development.
WEEK 3
-Remove runners from strawberry plants to direct their energy to fruit production.
-Keep asparagus harvested for continued spear production. Control asparagus beetles as needed.
-Begin planting sweet corn as soon as white oak leaves are as big as squirrel ears.
-Isolate sweet, super sweet and popcorn varieties of corn to prevent crossing.
-Thin plantings of carrots and beets to avoid overcrowding.
-Control caterpillars on broccoli and cabbage plants by handpicking or use biological sprays such as Bt.
-Set out tomato plants as soils warm. Place support stakes alongside at planting time.
-Sow asparagus peas 4 inches apart in drills 1 inch deep and 15-18 inches apart. When plants are a few inches high, support them with twiggy sticks.
-Counteract carrot flies by masking this vegetable's attraction to pest by growing them next to onions. -Alternatively, every two weeks scatter lawn-clippings between the rows.
WEEK 3 & 4
- Plant dill to use when making pickles.
WEEK 4
-Sow beet seeds ¾ inch deep in small clusters 5 inches apart in rows 12 inches apart. Later, thin them to one strong plant at each position.
-Sow endive ½ inch deep in drills 15 inches apart, and radishes ½ inch deep in rows 8-12 inches apart.
-Thin summer lettuces to 9-12 inches apart.
-Watch for striped and spotted cucumber beetles now. Both may spread wilt and mosaic diseases to squash and cucumber plants.
- Place a stake by seeds of squash and cucumbers when planting in hills to locate the root zone watering site after the vines have run.
- Remove rhubarb seed stalks as they appear.
Lawns
ALL WEEKS
-Keep bluegrass cut at 1.5 to 2.5 inch height. Mow tall fescue at 2 to 3.5 inch height.
WEEK 2
-Feed established lawns with a quick-acting lawn fertilizer at ½ cup/square yard.
WEEK 4
-Lawn seeds sown in April soon germinates and reaches 3 inches high, when it can be cut. Use a sharp-bladed mower and cut grass 2 inches high - no shorter. Do not use blunt mowers that tear young seedlings from the soil.
- Apply post-emergence broadleaf weed controls now if needed.
Miscellaneous
ALL WEEKS
-Birds eat many insect pests. Attract them to your garden by providing good nesting habitats.
-Water and mulch lilies. Ensure the soil is moist and free from weeds before forming a mulch 2-3 inches thick.
-Hedgehogs are a gardener's friend, eating slugs, beetles, cutworms and millipedes. Bread soaked in milk is a treat for them, especially in the fall when they need to gain body weight prior to hibernation.
-Purple martins return to the Lehigh Valley area this month.
WEEK 1
- Mole young are born in chambers deep underground.
- Honeybees are swarming. Notify a local beekeeper to find a new home for these beneficial insects.
WEEK 2
- Soaker hoses and drip irrigation systems help you save water and money.
- Hummingbirds return from their winter home in Central America.
- Wasp and hornet queens begin nesting.
WEEKS 1 & 2
- Look for morel mushrooms when lilacs bloom and the forest floor turns green.
- Herbs planted in average soils need no extra fertilizer. Too much may reduce flavor and pungency at harvest.
-Take houseplants outdoors when nights will remain above 50 degrees. Most prefer only direct morning sun.
-Watch for fireflies on warm nights. Both adults and larvae are important predators. Collecting may reduce this benefit.
-Sink houseplants up to their rims in soil or mulch to conserve moisture. Fertilize regularly.
WEEK 4
- Herbs planted in average soils need no extra fertilizer. Too much may reduce flavor and pungency at harvest.
Ornamentals
ALL WEEKS
-Apples, crabapples and hawthorns susceptible to rust disease should have protective fungicidal sprays applied beginning when these trees bloom.
-Pinch azaleas and rhododendron blossoms as they fade. Double flowered azaleas need no pinching.
-If spring rains have been sparse, begin irrigating, especially plants growing in full sun.
-Fertilize azaleas after bloom. Use a formulation which has an acid reaction.
-When all danger of frost has passed, plant gladioli (5-6 inches deep) in small groups, each corm about 8 inches apart. Before covering, insert stakes by the sides of each corm.
-Plant Ranunculus asiaticus tubers 2 inches deep and lily bulbs (usually about two-and-a-half times their depth) if the soil is workable. However, the Madonna lily is planted with its nose just below the surface.
WEEK 1
- Hardy annuals to sow outdoors, where they are to flower: Common Mignonette, Common Nasturtium, Evening-scented Stock, Love-lies-bleeding, and Summer Adonis.
WEEK 2
- Prune spring flowering ornamentals after they finish blooming.
- Begin planting out summer bulbs such as caladiums, gladioli and acidanthera at 2 week intervals.
WEEK 3
Continue monitoring pines, especially Scotch and mugo, for sawfly activity on new shoots.
Begin planting gladiolus bulbs as the ground warms. Continue at 2-week intervals.
Plant hardy water lilies in tubs or garden pools.
WEEKS 3 & 4
- Canker worms (inch worms) rarely cause permanent damage to ornamentals. Use Bt if control is deemed necessary.
- Don't remove spring bulb foliage prematurely or next year's flower productio
n will decline.
WEEK 4
-Begin planting warm-season annuals.
-Herbaceous perennials to outdoor sow in a seedbed: European Columbine, New York Aster, and Oregon Fleabane.
- Plant summer bulbs such as caladiums, dahlias, cannas and elephant ears.
- Scale crawlers are active now. Infested pines and euonymus should be treated at this time.
-Hold off planting warm season vegetables, such as tomatoes, eggplants, vine crops; herbs, and warm-season annuals until the soil warms, usually in mid to late May.
-We've had warm temperatures and then some hard frosts. Some ornamental plants have been affected by frost damage. The damaged parts can be trimmed away and the plant will regrow.
-Continue to inspect for and treat for holly leafminers as new leaves emerge.
-Keep a watchful eye for Spotted Lanternfly egg masses and destroy any you find
. SLF nymphs have begun to hatch.
Egg masses are live and viable from about October through July. You can scrape them off of trees or smooth surfaces.
Bottom line with SLF: Kill them if you can. Use recommended practices. Don't move them around.
-Collect and dispose of bagworms as well as cedar-apple galls on junipers befo
re the orange spore-producing structures emerge from the galls.
-Apply protective sprays on apples and hawthorns for rust disease if warranted.
-Do not prune apples and other plants susceptible to fireblight at this time of year
as
you can spread the disease. This also applies to black knot, which affects plums and other member in the Prunus genus.
-Check pines and junipers for signs of tip blight. Spaeropsis tip blight and Kabatina blight are common in the St. Louis area. Cankerworms may be observed at this time of year but they usually do little damage and do not warrant control.
-Monitor pines for sawfly damage. Also check for crawlers of euonymus and pine scales.
-Treat for borers if found in dogwood, ash, lilac, apple, and peaches. Apply a preventative insecticide spray to the trunks of peach trees and other stone fruits in the first half of the month to control peachtree borers. Apply again in August.
-Scout for slugs, which chew holes in leaves and cutworms, which can cutoff young plants at ground level. The rose slug can cause damage to roses.
-Watch for sod webworms towards the end of the month.
-Treat broadleaf lawn weeds if warranted while they are still actively growing. Weeds are more difficult to kill with herbicides as their growth slows when weather warms.
-Monitor azaleas for early signs of lacebug damage.
-Scout for eastern tent caterpillars and destroy webs if found.
-If boxwood leaves are infested with leafminers, some control can be obtained by pruning the plants back and disposing of the leaves before the adults hatch in late May. The boxwood psyllid causes cupping of leaves.
-Other problems to be on the lookout for are anthracnose of sycamore and the taxus mealybug.
-Watch for Red Thread in turf grasses. Cool, wet periods with malnourished turf provide
the best opportunity for disease.
-Indoor plants moved outside for the summer are very susceptible to sunburn and wind whipping. Acclimate plants gradually to outdoor conditions to avoid setting them back or damaging tender new growth.
-Be on the lookout for asparagus beetles.
-Do not harvest and eat rhubarb that has been damaged by a late frost.
If you are unsure of pests or problems you may be having, please call to help get a diagnosis.
