June Garden Checklist

General Garden Care

· Mulch all garden beds after thoroughly weeding and watering. Use 2 to 4 inches of shredded bark on perennial and flower beds and larger chips around tree root zones. Mulch conserves moisture, protects the root zones of plants and helps keep weeds down.

· Make sure all newly planted trees, shrubs, perennials, roses, etc. are watered deeply once a week.

Woody Plant Care

· Fertilize roses with a second application of a liquid 20-20-20 fertilizer after the first flush of flowers. Continue to monitor for black spot. Remove infected leaves immediately and begin spray program with an approved fungicide. Most products must be reapplied following any rainfall.

· Deadhead hybrid tea roses as soon as flowers fade. Some shrub roses are self-cleaning and don't require deadheading. When in doubt, lightly prune old blossoms to keep plant looking attractive.

· Pinch off 1 inch of sticky new green growth on azaleas and rhododendrons to increase next year's flowers. Mulch acid-loving plants with shredded pine needles and/or shredded oak leaves.

· Continue to prune all spring-flowering shrubs immediately after they flower.

· Fertilize lilacs for the second time, after they flower, with a dilute 10-10-10 fertilizer. Lightly prune blossoms off as they fade.

· Small evergreens such as boxwood or yew can be lightly pruned to maintain formal character.

Annual and Perennial Care

· When cutting peony blossoms to bring indoors, remove as few leaves as possible from the plant. Don't cut more than 25 percent of the flowers from one bush and avoid cutting flowers from newly planted peonies.

· Deadhead annuals and perennials to encourage new flowers.

· Stake tall perennials and continue to tie annual and perennial vines to supports. Encourage multiple stems of clematis vines to climb horizontally as well as upward. Tie stems with soft cloth if necessary.

· Fertilize annuals in containers, baskets and window boxes with a quarter-strength balanced fertilizer every seven to 10 days. Always water the plants before adding liquid fertilizer.

· Fertilize bulbs with a 9-9-6 slow-release fertilizer if you did not do so at planting time. Mark the spots with small stakes so repeat application of fertilizer can be made in fall (when bulbs are not visible).

· Continue to remove yellowing leaves of summer-flowering bulbs.

· Amaryllis plants should be placed in morning sun and fertilized twice a month with a 15-30-15 liquid. Leaves will continue to grow all summer as they manufacture food for the bulb. Don't forget to water the bulbs.

· Sow seeds of perennials directly into the garden this month for next year's bloom. Mark the spots carefully.

· Monitor succulent new growth for signs of aphids (puckered stunted leaves). Hose down affected plants. Don't use strong chemicals if ladybugs are present since they are predators of aphids.

· Hot, dry weather can result in increased mite activity. Symptoms include stippling of foliage. Remove affected foliage. Strong miticides will also kill beneficial mites.

Lawn Care

· Monitor lawn for weeds. Rain and warm water will push grass to grow fast. Mow high (2 to 2-1/2 inches) in hot, dry weather so individual blades of grass can shade each other. Try to leave grass clippings on lawn, but avoid clumping.

· Seed bare areas of lawn with appropriate grass seed mix and starter fertilizer. Keep area moist until seeds germinate. Do not mow for several weeks as new grass thickens up.

· Do not fertilize lawn in hot weather. Best time to fertilize is fall.

· Water lawns, if necessary. Grass can go dormant for several weeks in intense heat and requires only 1/2 inch of water to keep crowns alive. Avoid watering midday or on windy days. Soaker hoses are a direct and efficient method of watering.

· If grubs have been a problem in past, treat affected areas with a product containing imidacloprid. The best time to apply in Chicago area is mid- to late June. Water in well.

Fruit, Vegetable and Herb Care

· Stake or cage tomatoes as they begin to grow.

· Harvest peas, raspberries and all cool-season lettuces and vegetables as they ripen.

· If squash vine borer has been a problem in your garden, cover small transplants of squash, cucumbers and zucchini with row covers to prevent moths from laying eggs on vines. Remove row covers when plants begin to flower. Consider planting disease-resistant varieties next year.

· Pinch new top growth of herbs to keep them from flowering. This intensifies the oils and flavor in the foliage. Snip or cut off sprigs of herbs to use in cooking all season.

· Plant pumpkins at the first of the month. Large varieties require a 100-day growing season.

· In late June sow seeds of corn, bush beans and cabbage for an early fall harvest.

· Mulch vegetable garden with straw to retain moisture.

If you have questions or comments about this article, home gardening or about the Master Gardener program, please call the Master Gardeners c/o University of Illinois Extension, DeKalb County office at 815-758-8194 or email prescott@uiuc.edu .