Gardening This Weekend: August 9, 2018
I’ve boiled your “assignments” down to the precious few that are timed for early to mid-August. Scan through the list.
• Fall foliage color from copper plants, firebush (also has blooms) and purple fountaingrass or fall floral color from zinnias, marigolds and celosias. You may have to look a little bit, but whenever possible buy potted transplants that are in bud but not yet in bloom
• Dig and divide established daffodils, jonquils and narcissus before new root growth begins. If you’re going to be ordering more for planting in a few weeks, start shopping now.
• Cole crops. Set out vigorous nursery transplants, including cabbage, broccoli, cauliflower and Brussels sprouts.
• Salvia greggii and rose bushes by one-third to stimulate new growth. It’s on those new shoots that fall blooms will be produced.
Note to our DFW-area readers: Rose rosette virus is epidemic in and around the Metroplex. If you are growing roses in that area, check out the details I have on my website.
• Spent flower stalks, seedheads from annual and perennial plantings to keep landscape tidy.
• Flowers from coleus, basil, mint, caladiums and other plants where flower buds and flowers stop production of new foliage.
• Bermuda turf with all-nitrogen lawn food in which half or more of the nitrogen is in slow-release form.
• Do not fertilize St. Augustine for another 3-4 weeks to avoid late-season outbreak of gray leaf spot (fungus that is exacerbated by applications of nitrogen). I’ve had many posts asking about gray leaf spot on my Facebook page. Here is a story we had on it recently here in e-gardens. Note the irregular patches of yellowing grass that rarely die out completely.
• Iron-deficient plants. Look for yellowed leaves with dark green veins, most prominent on newest growth first. Apply iron with sulfur added. Function of the sulfur is to acidify the soil so that the iron will remain soluble as long as possible.
• Water-soluble, high-nitrogen plant food to container plants including hanging baskets. Nutrients are not retained very long with frequent irrigation and lightweight potting soils.
ON THE LOOKOUT
• Chinch bugs have been terrible on St. Augustine this summer. Big areas first look dry, then dead and brown in spite of watering. Get down on your hands and knees in the hottest part of the afternoon. Look at the interface of the dying and healthy grass. You’ll probably find small black insects flitting around there. Look for irregular white diamonds on their backs. Treat with a labeled lawn insecticide.
• If you have nutsedge (nutgrass) in your lawn, this is almost your last call to apply Image or Sedgehammer to eliminate it. Both products need several weeks of warm soils to complete their work.
• Leafrollers are attacking vinca groundcover and several types of shade trees and shrubs, also cannas. They roll up the leaves or tie them together as protection. Systemic insecticides will stop them, but only if applied 2-3 weeks prior to their arrival. It’s probably too late for this season.