May Gardening Tips for the South
Prune Climbing Roses
After climbing roses finish flowering, prune canes back to 4 to 5 feet long. It's also an ideal time to train new growth to wrap around supports. You'll be rewarded with more flowers!
Inspect for Disease
Keep an eye on rose bushes for powdery mildew and black spot symptoms. Treat infected plants with a fungicide. To help control these diseases, water roses early in the day. Delivering water directly to soil -- instead of overhead watering that wets foliage -- is ideal.
Also, be sure to gather any fallen rose leaves. Don't compost infected leaves; throw them in the trash to prevent disease from spreading.
Continue to fertilize roses. You can choose from several ways to feed your roses.
One of the most common is to use liquid fertilizer -- just mix a powder or liquid form with water and apply every two weeks until late August.
Or make it easy and select a slow-release fertilizer. Simply scratch one of these products into soil surrounding roses every 6 weeks.
Or improve the soil while fertilizing your roses by adding a spadeful of compost to your soil every month. Don't heap it against canes, but spread it over soil beneath the plant.
Test Garden Tip: Some rose fertilizers are pre-blended with a pesticide to feed plants and fight pests at the same time. With products like these, make sure you read the label carefully. The pesticide will likely also kill beneficial insects and butterflies.
Growing Herbs in the South
You don't need a formal herb garden to enjoy the scents, flavors, and beauty of herbs. Incorporate herbs into existing planting areas.
Dill and fennel, for example, add a fine, airy texture to vegetable gardens and flower borders. Their flowers beckon beneficial insects. If you permit plants to set seed, volunteer seedlings will emerge next year.
Or, use herbs as an edging in your landscape. 'Spicy Globe' or 'Boxwood' basil,for instance, or parsley form an ideal edging for a formal planting; use chives or tricolor sage for a playful touch and change in texture. Tuck thyme at the front of the border or along a rock wall.
Be sure to include Mediterranean herbs -- rosemary, thyme, and lavender -- in unglazed terra-cotta pots. The porous pots keep roots on the dry side.
If you love cilantro, plant a new crop of seeds every couple of weeks throughout the summer. This plant doesn't last long in summer heat -- so by replanting, you'll always have a fresh crop.
Test Garden Tip: The more you pick herbs, the more you'll have to harvest. Plan ahead for meals and gather herbs early in the morning when flavors are strongest. Stash stems in water until cooking time.
Growing Vegetables in the South
Across the entire South, all warm-season vegetables should be in the ground this month: tomato, pepper, okra, eggplant, squash, melon, corn, and cucumbers.
Plant beans, too! Grow a variety so you have some to eat fresh and others to dry for use later.
All About Tomatoes
Dig extra-deep planting holes for tomatoes. Fill the bottom of the hole with nutrient-rich materials. By supplying extra calcium, you'll keep blossom-end rot at bay.
A handful of bonemeal and three to four crushed eggshells come next. Both are excellent sources of calcium.
Stake your tomatoes to keep them growing upright throughout the season.
Test Garden Tip: Remove bottom leaves from tomato stems and bury the lower stem. Roots will generate along the buried stem. If you can't dig a deep hole, dig a trench, and lay the seedling in the planting hole on its side, arranging the leafy top where you want the plant to be above ground.
In all but the hottest regions of Texas and Florida, continue to plant container-grown trees, shrubs, perennial herbs and flowers, and groundcovers.
If you haven't already, move your houseplants outdoors to a shady spot. It's a good time to repot and fertilize them to ready them for a summer growth spurt.
Inspect the underside of camellia leaves for red spider mites and scale. If you spot either, apply horticultural oil.
Because the plants have shallow root systems, it's important to keep them well watered, especially during hot, dry periods. Adding a 2-inch-deep layer of organic mulch now will help the soil stay moist longer once hot summer weather arrives. (Mulch will also help keep the camellia roots cooler.)
Run your irrigation system before summer heat arrives. Replace any damaged sprinkler heads and inspect water delivery to ensure it's being delivered to planting areas or lawn -- and not pavement.
Apply a sulfur-coated fertilizer to gardenias and azaleas. Use an all-purpose formulation and follow label directions.
Fertilize warm-season turf grasses. Zoysia and warm-season Bermuda prefer high-nitrogen fertilizers. Centipede grass needs little fertilizer and minimal nitrogen.
Before planting, add fertilizer to planting beds for annuals or vegetables. Or wait until plants have been actively growing two weeks, and then work fertilizer lightly into soil.
Tackle poison ivy and other perennial weeds early in the season. Apply products containing the active ingredients glyphosate or triclopyr. Follow label instructions carefully and take precautions to cover your skin when treating poison ivy. Wear gloves, long sleeves, and long pants to avoid a reaction.
Put on a Summer Show
Plant cannas to add vertical interest to the garden. Try types with colorful foliage -- either the traditional burgundy-leafed cannas, or variegated ones.
'Pretoria' canna is a favorite; it unfurls leaves pin-striped with green and creamy-yellow/chartreuse.
Tropicanna canna features leaves that offer vivid stripes of pink, yellow, red, gold, chartreuse, and green. For a breathtaking show, plant Tropicanna where it will be backlit.
'Stuttgart' canna foliage bears striking white blotches along leaf edges. The effect mimics that of variegated ginger, but with more upright growth.
Plan for Autumn
Although summer is just getting started, take advantage of good planting weather and ensure your garden looks as great in autumn as it does now.
Add fall-peaking plants to garden beds, including Mexican bush sage, asters, boltonia, Japanese anemone, and helenium.
Or consider ornamental grasses such as pampas grass, 'Morning Light' miscanthus, sea oats, pink muhly grass, switchgrass, and sedge species.