August is a time for picnics and barbeques, trips to the beach, and family vacations. But for the devoted gardener, summer offers little rest from routine chores. Here are a few items for the August gardening calendar:
Shrubs and Trees
- Shade trees showing fall color in August may have root or trunk damage. Inspect the tree for damage caused by digging near the tree, injury from soil fill placed over the root zone, chemicals in the soil, excess water (or too little water), and girdling roots growing across others or cutting into the trunk; all can be serious problems.
- August is a month of "do nots" for tree and shrub care. Do not fertilize, do not prune. Pruning and fertilizing in late summer may stimulate new growth that may not harden off properly for winter. Wait until October to do these chores.
- Mid-August through mid-September is traditionally the best time to establish new lawns. Soil temperatures are still warm enough to get good germination, but most perennial weeds will not have time to "harden off" and will die over winter. Fewer weeds for your lawn to compete with insure a better quality lawn next spring.
- Once a lawn area is seeded, maintaining adequate moisture is critical for success. Emerging grass seedlings die easily if they go under drought stress. Put down light mulch, such as straw, to help maintain moisture.
- Between August 15 and September 15, aerate lawns with a heavy thatch layer (greater than 1 inch), newly sodded lawns, and lawns that have had infestations of necrotic ring spot. Use a core aerator and leave the cores on top of your lawn to dry; after several days of dry weather, the cores will be dry enough that the lawn mower will do an adequate job of pulverizing them.
Perennials, Annuals, and Bulbs
- Continue routine maintenance on annual flowers to keep plants productive for the balance of the season. Remove spent blooms on a regular basis to keep new blooms coming. Water plants during dry spells, and possibly give them a little balanced fertilizer at the same time.
- Azaleas, rhododendron, and other ericaceous (acid-loving) plants need to be fertilized one more time before the end of August using an acid-based soluble fertilizer containing iron.
- The two most common reasons for geraniums not blooming prolifically are too little light or too much fertilizer. Too much fertilizer and you will get large, lush green plants and few blooms. With geraniums, it's better to under feed than over feed.
- Start thinking about planting for fall color and develop a planting plan.
Fruits and Vegetables
- Harvest vegetables as they ripen; overripe fruit on a plant will prevent the smaller fruit from developing.
- Earth up Brussels sprouts (to give them support as they mature) and main crop potatoes (to give an increased yield).
- You can dig potatoes when the tops begin to yellow. Take care not to overwater potatoes for the rest of the season.
- Prune away excess vegetation and new blossoms on tomatoes after mid-August and concentrate on ripening set fruit.
- To keep those cute little bunnies from treating your garden as an all-you-can-eat buffet, put a teaspoon of cayenne pepper and a spot of dish soap into a spray bottle with water. Spray your plants, and the bunnies will dine elsewhere!