Monthly Gardening Tasks - September

When you add new woody plants (dogwood, holly, pyracantha, viburnum) to your garden this fall, avoid fertilizing them at planting time. Give them time, until at least the spring, for their roots to become established before you start feeding them.

This is the last month to safely fertilize warm-seasoned grasses such as St. Augustine and Bermuda. If you want green grass in the winter, use perennial rye.

Feed and water your roses and keep an eye out for spider mites or fungal problems.

Plant your wildflowers now because they require some period of cold weather before they germinate. Loosen soil. Scratch the seeds. Cover with light soil to protect from birds. Water gently.

Plan to plant wildflowers in early September and October. Check supplies now and order seed for planting in open sunny areas. Consider bluebonnet, Indian paintbrush, coneflower, fire-wheel, black-eyed Susan, evening primrose and many others. Keep plants on the dry side for a month prior to the treatment.

Plant Iris, daylilies and canna’s in full sun or morning sun in a well-drained spot. You will find that all three of these flowers are low maintenance.

Fall webworms can be a problem this month and next on your pecan trees. If you can safely reach them, prune out the webs as soon as you see them. Aphids may also still be appearing on your pecan trees this month. Aphids can be harder to see than fall webworms, but the sticky honey dew they produce fall on cars and isn’t hard to miss. Releasing ladybugs on aphid-infested trees is usually the best way to control these pests.

Rejuvenate heat-stressed geraniums and begonias for the fall season by lightly pruning, fertilizing and watering.

Caladiums require plenty of water this time of year if they are to remain lush and attractive until fall. Fertilize with ammonium sulfate at the rate of 1/3 to 1/2 pound per 100 square feet of bed area, and water thoroughly.

Don't allow plants with green fruit or berries to suffer from lack of moisture. Hollies will frequently drop their fruit under drought conditions.

Remove weak, unproductive growth and old seed heads from crape myrtles and roses to stimulate new growth for fall beauty.

Prune out dead or diseased wood from trees and shrubs. Hold off on major pruning until mid-winter. Pruning now may stimulate tender new growth prior to frost.

Sow seeds of snapdragons, pink, pansies and other winter flowers in flats for planting outside during mid-to-late fall.

Prepare the beds for spring-flowering bulbs as soon as possible. It's important to cultivate the soil and add generous amounts of organic matter to improve water drainage. Bulbs will rot without proper drainage.

Contain a disease spray schedule on roses as blackspot and mildew can be extremely damaging in September and October.

Christmas cactus can be made to flower by supplying 12 hours of uninterrupted darkness and cool nights (55 degrees) for a month starting in mid-October. Keep plants on the dry side for a month prior to the treatment.