7 Essential Tasks for Late Summer Flower Garden Care

July Flower Garden
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July and August are months when flower gardeners should be enjoying the fruits of their labor. Unfortunately, high summer temperatures and drought conditions sometimes bring a premature end to the garden's beauty. Renew the late summer garden's vigor with these flower gardening tips. 

Time to Plant

Most flower gardeners are finished wth their planting tasks after the summer solstice. However, there are some benefits to planting in late summer. The biggest bargains are found in the garden aisle after July 1st. And, if you skip the big box store and head to a dedicated plant nursery, the flowers will probably be in good shape. If the annuals look a little scraggly, some pruning and a good drink will perk them up. Rootbound perennials may get a slower start in the garden but should be recovered by the time fall rains arrive. The only plants you should avoid are leftover cool weather plants from spring-like pansies or violets, which will not regain their former glory. Purchase fresh stock in the fall for these short-season plants. 

With fall just around the corner, consider starting cool weather fall flowers from seed in mid to late July. Nasturtiums, snapdragons, and flowering kale keep the garden beautiful into October. Start seeds outdoors in a shady spot, and be diligent about keeping the seeds and seedlings moist. If your region is just south of Hades, start your seeds indoors, and move transplants outside after temperatures moderate. 

Keep Weeds Away

Weeding is a satisfying task in the spring when moist soil and small weeds permit the gardener to make quick work of unwanted plants. However, when temperatures soar and tough perennial weeds send roots deep into summer-baked soil, the gardener may be tempted to give up on weed control. Repeated cultivation with a hoe at least twice a week will weaken established weeds. If it's not too hot to work safely in the yard, the gardener should at least attempt to remove the seed heads from weeds that will germinate when cool temperatures and fall rains return. 

Stop Insect Pests

Gardeners breathe a sigh of relief when typical spring pests like aphids fade from the landscape. However, summer insect pests like beetles, spider mites, scale, whiteflies, and grasshoppers soon replace them. Take advantage of cool mornings to conduct landscape rounds, plucking off the larger offenders and dropping them in a bucket of soapy water. Use any pesticide sprays judiciously, whether organic or conventional, as sprayed foliage is susceptible to burning in high temperatures. Yellow sticky traps are an easy way to capture thrips, fungus gnats, and whiteflies. Spider mites gravitate to drought-stressed flowers, so a daily misting will discourage these pests. 

Control Diseases

Flowers weakened by drought stress and high temperatures are vulnerable to mildew and fungal diseases. High humidity and nighttime temperatures further encourage the development and spread of plant diseases. Gardeners should remove and destroy any leaves infected with black spot or mildew, as spores will settle into the soil, only to reappear next season. Selective pruning of overcrowded branches promotes disease-reducing air circulation. 

Keep Feeding

Some flowers need regular nutrient boosts to keep blooming until the end of the season, while others need to harden off and rest. Annual flowers, especially those that shine at the end of summer like dahlias, need continuous feeding until frost. You should allow perennial flowers to naturally wind down their blooming season, without forcing further new tender growth with fertilizing. If your garden features flowers that throw a second flush of blooms when the weather cools, like roses, you should apply the last feeding at the beginning of August. 

Check Your Mulch

Even when gardeners lay down a 3-inch layer of organic mulch in the spring, moisture and high temperatures can cause the mulch to break down before the garden season ends. Without a protective layer of mulch, the surface of the soil becomes cracked and hardpan and the delicate feeder roots of flowers wither. Gardeners should apply a fresh layer of mulch in mid to late July, keeping the application a few inches away from plant crowns.

Water Wisely

Flowers need a minimum of an inch of water each week during summer months, but up to 3 inches of water when temperatures hover around the century mark. Conserve water by using soaker hoses, and water early in the morning to allow foliage to dry quickly.