Gardening This Weekend: August 20, 2020

You might not have realized it, but this ought to be one of the busiest times of the gardening year. Here are the most critical jobs for the upcoming weekend.

PLANT
• Leafy and root vegetables, including lettuce, spinach, collards, beets, turnips and radishes, among others.
• Last call to find crape myrtles in good bloom in local nurseries. It’s always best to buy them in flower to be sure you get the colors you want.
• Just about last call for seeding bermuda. Soils will begin to cool in the next several weeks and the grass won’t develop properly.
• Wildflower seeds, particularly bluebonnets. They need the early fall rains to germinate and establish good roots going into the winter, so they can burst into full bloom as spring unfolds. Buy acid-scarified seeds for most uniform germination.

PRUNE
• Seed heads, browned foliage and spent flowers from perennial gardens. Leave green foliage intact, but it’s always OK to trim off dead leaves.
• Root-prune trees and shrubs you intend to transplant this winter. By trimming their horizontal roots now by cutting a slit with a sharpshooter spade, you will give them several months to establish new roots within what will become their soil balls when you dig them.
• Root-prune wisterias that have failed to bloom in years past. Use a sharpshooter spade to sever lateral roots 15 to 18 inches out from the trunk. Do not attempt to cut any deeper roots.
• Mow at the recommended height. Raising the mower blade, in spite of what others may tell you, improves neither summer durability nor winter hardiness.

FERTILIZE
• Iron chlorosis. Almost last chance to correct iron deficiency for this growing season. Add iron/sulfur amendment. Keep granules off concrete and masonry to prevent staining.
• Annual flowers with high-nitrogen food if plants have become lethargic and shy about blooming.
• St. Augustine in a week or two, probably for the first time since early summer. That’s because gray leaf spot outbreaks will abate as temperatures cool.
• Bermuda turf if it’s been more than 8 or 10 weeks since last you did. Use an all-nitrogen food containing upwards of half of its nitrogen in slow-release coated or encapsulated form.

On the Lookout
• Pre-emergent weedkiller applications must be made between the next week or so and Labor Day. See related story this issue.
• Leaf scorch (browned leaf edges and tips). This is evidence of moisture stress at some point during the summer. If there has been no injury to trunk or roots, your solution is to keep plant uniformly moist at all times.
• Keep an eye on developing cabbage, broccoli and other Cole crops for holes in leaves caused by cabbage loopers. Apply Bacillus thuringiensis biological worm control at first evidence.