August is ripening grain in the fields blowing hot and sunny, the scent of tree-ripened peaches, of hot buttered sweet corn on the cob. Vivid dahlias fling huge tousled blossoms through gardens and joe-pye-weed dusts the meadow purple.

– Jean Hersey

The dog days of summer are upon us, and the gardens can be a mixed bag of abundance, rot, beauty, and wilt. There is more to late summer than watering and weeding. Now is the time to prepare for fall and to plant the bulbs and seeds that will blossom and flower next spring. It’s not too late to take in the colorful, textured scenery provided by some of August’s top flowers and plants: dahlias, showy sedum, Mexican bush sage, ornamental grasses, and end-of-the-month garden chrysanthemums. Get busy now and be prepared for the upcoming seasons. But make some time to sit in the shade and enjoy the fruits of your labor.

General Tips

Composting and mulching help to beat the heat and weeds, and prepare your gardens for fall planting. Water deeply but strategically at the base of plants in the early morning or early evening. During dry spells, soak shrubs enough to moisten the soil 8-10 inches deep. Don’t neglect to water your trees, even if they have been around for ages. Hanging baskets and containers dry out quickly and will need watering at least once or twice a day in the heat of this month.

Using larger containers and a soilless potting mix, repot houseplants that have spent the summer outdoors and move them back inside to adjust to less sun exposure. August presents your last best chance to heavily prune hedges and evergreens and have them harden off before going dormant in late fall. Late trimming might result in new growth vulnerable to freezing.

Flowers and Herbs

To encourage more blooms and thicken up stems, deadhead, cut back, and feed flowers and roses. Divide and transplant bloomed spring and summer-blooming perennials. Replacement annuals can freshen up the flower show and offer an opportunity to experiment with growing ones you’ve never tried before. Mid-morning hours are best for taking cuttings for new plants or gathering herbs and flowers for drying and preserving, after the morning dew has dried but before the wilting heat of the afternoon. Herbs can also be made into pesto and frozen.

Start pansy seeds indoors and plant outdoors once grown for spring blooms. Poppy seeds can now be sown directly into the ground for next year’s beautiful flowers. August is a perfect time for ordering autumn flower seeds and shopping for bulbs. Planting flowers and garlic from bulbs in the fall will yield a fine harvest in springtime. Use plastic golf tees to color-code and mark the location of all these dormant plants.


Harvest your produce and hoe often to deter weeds. Share with neighbors if you won’t eat it all. Remains of harvested crops can now be tilled under or composted. Keep the fresh salads coming by planting more lettuce and spinach, along with radishes, turnips, and beets. Planting a fall crop of peas late in the month and twice as deep will fix nitrogen into the soil for planting in the spring. Freezing shelled peas can bring you a taste of spring in the dead of winter. Plant fall vegetable starts and transplants.    


Cover plants with netting to protect ripening fruits. Thornless blackberries and fall-bearing red raspberries are ripening now. Help prevent insect infestation by removing any fallen fruit from fruit trees. Fertilize citrus trees after harvesting.

For reference, Louisville is located in USDA Plant Hardiness Zone 6b.

Posted on 2020-08-05 by By Dawn Anderson