The lazy days of summer arrive in July. Don't overdo it when the weather is hot and steamy, which is to say most of the time. Stay out of the midday heat and save any gardening tasks for the early morning or early evening. Dress coolly, take frequent breaks, have plenty of water on hand and drink frequently. Here are a few items for the July gardening calendar:
Shrubs and Trees
- Don't fertilize trees or shrubs, especially fruit trees, after mid-July. Fertilizing will encourage new growth that will not harden off in time to avoid winter injury.
- Water newly planted shrubs and young trees (planted within the last three to five years) during dry weather. Allow water to penetrate to a depth of 8–10" rather than sprinkling frequently and lightly.
- Keep shrubs and trees mulched to a depth of at least 4" to conserve moisture and cool roots. Don't mound mulch directly against tree or shrub trunks, but keep it about 2" away.
- Remove sucker growth from the base of trees and along branches.
- Scout ornamentals, trees, and shrubs for damage caused by spider mites. Spider mites prefer high temperatures, little or no rainfall, and little or no wind. Spider mites are particularly fond of spruce and arborvitae, sucking plant sap and making the growth look yellow. To test for spider mites, hold a piece of white paper horizontally under a discolored branch. Tap the branch vigorously; if several very small "dots" begin to move on the paper, you likely have spider mites.
- Leaf scorch can occur when water cannot be moved to tree foliage as rapidly as it is lost. Scorch will not kill a tree, but watering will relieve the browning on edges of leaves.
- Avoid "lawn-mower blight" — be careful to avoid nicking tree trunks while mowing.
- Fertilize lawns this month for the last time before September. Lawns go somewhat dormant in the heat and do not need fertilizer, but they do need water.
- Water deeply and less often for deep roots and a healthy lawn. When the top one or two inches are dry, saturate the lawn to a soil depth of five or six inches.
- Mow regularly to prevent weed seed spread. Don't mow your lawn in the same direction every time, but vary your path so that the turf and soil don't form compacted mower ruts.
- Raise the lawn mower height of cut to keep lawn greener and put less stress on the grass. Don't remove clippings from the lawn unless grass is excessively tall or weedy. Clippings return nutrients to the soil and do not add to thatch buildup.
- Check lawns for newly hatched white grubs. If they begin to hatch, the garden experts at Reds will be happy to help you find the right grub control products for your lawn.
- Weeds overtaking your lawn? To identify and control unsightly weeds, check out the Midwestern Turfgrass Weed Identification and Control website.
Perennials, Annuals, and Bulbs
- Continue to deadhead most annuals and perennials and keep your beds watered. Remove faded blossoms from annuals to stimulate more flowers for late summer color, and from perennials to prevent reseeding.
- All garden plants need water, but hanging baskets and container plantings are particularly susceptible to drought. Check the moisture level in containers often during summer months; containers may need watering two times a day when temperatures get into the eighties or nineties. Continue to turn hanging baskets 180º every few days to ensure fullness and uniform growth.
- After the spring bloom your plants need a boost to bloom again or to go into their growing cycle. Use slow release fertilizer on permanent plantings and liquid fertilizer on annuals, pots, and hanging baskets. Don't fertilize perennials after mid-July, but allow plants to slow down and proceed with a buildup of needed reserves for winter.
- Remove flower stalks from peonies and iris and prune roses after bloom. Stake other tall-growing perennials (dahlias and gladiolas) to prevent them from sagging once in bloom.
- Once spring-flowering bulbs have matured and the foliage has turned brown, it is time to spade them up and thin out the stand. Crowded bulbs produce fewer and smaller blooms. They usually need thinning every 3 to 4 years.
- Early detection is the key to controlling disease and insect pests (powdery mildew, black spot spores, earwigs, slugs, etc.). Carefully inspect your garden, note any problems, and check with Red's expert staff for recommended control measures.
- Spireas that have pink flowers can be pruned to stimulate a second bloom in August and September. Do NOT shear white flowering spireas; they have different growth habits and won't rebloom.
- If you've been pinching back your mums throughout the spring, mid-July is the last time to pinch. If you haven't been pinching your mums all spring, here's an easy care trick: cut them back by half in early July and fertilize. This will help them to grow bushier and delay bloom until later in the summer.
Fruits and Vegetables
- Tomatoes, peppers, cucumbers, and squash should just be putting out the first good yields. Harvest promptly in the cool of the morning for best flavor and production.
- Start cutting and drying herbs for kitchen use. Frequent cuttings help encourage new growth.
- Don't harvest rhubarb or asparagus after July 1st. The plants must have foliage to bring energy into the rootstocks to survive the winter and remain vigorous for next season.
- Start seeds for fall vegetables this month. Sow beets, carrots, peas, parsnips, rutabagas, Brussels sprouts, cabbages, broccoli, cauliflower and salad greens by mid-July.
- Fertilize June bearing strawberries after the harvest, and ever-bearing varieties halfway through the season. Cut the fruiting canes of raspberry and blackberry plants at ground level after the harvest is over.
- After vegetables and herbs have established their root systems, fertilize with a good quality, slow-release vegetable food. Keep the garden watered and moist to avoid stressing plants.
- Control weed growth to preserve water and nutrients, and be on the lookout for garden pests and diseases.