Groom Your Garden When the Heat is On

By Vicki Spencer, Master Gardener

By August, when summer is in full force, leaves on some plants start wilting in the intense heat. Flower blossoms are beginning to die and lawns are taking on a brownish hue. You might feel like the gardening season is coming to an end, but there is still a lot to enjoy and plenty of work to do before winter.

Hot daytime temperatures may discourage you from doing much of anything, especially any gardening that involves hard labor. But this is a good time to take advantage of longer daylight in the mornings and evenings to groom and weed your gardens. If you are a night owl, you might balk at the thought of getting up early, but you might be surprised how gratifying it is to look over your garden just after sunrise with a cup of coffee in hand. It’s one of the most peaceful times of the day; the perfect time to relax, listen to bird songs and enjoy cool breezes while planning the day ahead. It’s also a good time to water your garden.

Although plants may look thirsty, most plants only need about an inch of water per week. Avoid watering in the middle of the day when most of the water evaporates before hitting the ground. Also avoid light surface watering, which also wastes water. It evaporates quickly from the top of the warm soil, so it never reaches the roots where it is needed. Watering less frequently and practicing deep watering encourages roots to grow deeper and plants are less likely to dry out. Deeper roots also help anchor the plants into the ground.

If you are not sure how much water your garden needs, use a trowel to dig down into the soil a few inches. Ideally the soil will be moist about 3 to 4 inches down. For hanging baskets or patio containers, push a finger deep into the planters to see if you feel any moisture. If not, it’s time to water thoroughly.

Annuals that look leggy and worn out should be cut back and fertilized to encourage new growth. Mums and other fall-blooming perennials especially benefit from one more feeding before fall. Most roses should receive nitrogen fertilizer after midmonth. Deadheading both annuals and perennials gives flower gardens a fresh look, and pinching off side shoots of dahlias encourages bigger flowers.

In mid-August, start dividing spring-flowering perennials, such as lilies, bearded iris, bleeding heart and bloodroot, to fill in bare spots. Plan to work in the coolest part of the day, dig up as much root as possible and discard old center sections and borer-damaged parts. While moving plants around, identify bare spots where you want to fill with more bulbs, then start ordering bulbs for fall planting.

During extended dry spells, soak shrubs instead of just sprinkling their leaves. Again, get the water down to the roots where it will do some good. While watering shrubs, look them over and decide if they need pruning to improve their shape.

If you have summer-blooming shrubs, just do some light pruning and wait until they finish flowering to clean them up for fall. Pruning hybrid roses encourages fall blossoms. Remove about one-third of the vigorous growth, any stems that cross each other, as well as any canes that were damaged by black spot fungus. This is also a good time to transplant any evergreens you want moved.

By August you have the pleasure of enjoying the harvest from your vegetable garden, but it too needs some tending. For example, it’s a good time to pinch the tops of tomato bushes to concentrate growth into the established fruit. It’s also a good time to plant another crop of green onions, lettuce, spinach, beets and radishes. If you want to enjoy herbs later in the year, take cuttings now, place them in moist, well-drained potting compost and put them in a cold frame. This works particularly well with rosemary, sage and mint.

Gardening is something you can enjoy throughout the summer and well into the fall. It’s especially fun when you can eat your vegetables and bring cut flowers into the house. So even though things may slow down in the dog days of summer, there is still plenty to do.