Harvest seeds that are ripe but not so ripe the seed heads drop or spew seeds to the ground.
Ripe seeds are usually dark.
When the vegetative envelopes swelling at the base of spent flowers begin to yellow and dry up, you can begin to harvest. Place the open end of a paper bag under a seed head, and snip it into the bag.
• Water deeply but not frequently for established plants. Do not water for brief periods every day or every other day – doing so can encourage fungal growth on the constantly wet surface and yet keep deeper roots dry, since the water doesn’t soak in very much and some of it evaporates. Plus, watering that often wastes water. The best way to water is to soak thoroughly. Soaker hoses and drip systems are best, sprinklers are second-best and hand-held hoses will do if you must. Just make sure the root area is well soaked and that the water seeps into the soil at least 4-6 inches deep. A guideline is to put down at least an inch of water, so if you use a sprinkler, measure how long it takes to fill a shallow can or dish about one inch deep. Remember that if nature does not provide water then your plants are counting on you!
• Do not let annual flower heads go to seed. “Deadhead” the plants — lip or pinch off spent flowers. This keeps the plants from exerting energy to produce seed and enables them to produce more flowers. You can let some flower heads go to seed if you want them to reseed and come up again next year. Be mindful of the fact that seeds from hybrid annuals do not produce offspring that are true to the original plant.
• This is your last chance for any needed pruning or wait until early winter to resume shaping shrubs or trees. Fall pruning can lead to a last-minute flush of tender growth that will be easily frost-killed and waste the plant’s energy.
• Start thinking about your fall garden now. August is the time to clean up the old vegetables in your garden and get ready for the new. In the fall garden you can have leafy vegetables, head vegetables, and underground vegetables. Mid-August to Mid-September is the time to plant your fall vegetables. Here are some great fall vegetables to look for: broccoli, cabbage, Brussels sprouts, kale, cauliflower, collards, mustard, turnips, lettuce, and more.
• The old canes should be cut from black raspberries and June bearing red raspberries now that the fruiting season is over. Removal of the old canes of ever bearing/fall red raspberries should be delayed until after mid-October.
• Avoid mosquito problems by turning over any pots, lids or saucers that might collect water and create a breeding site. Also check clogged house gutters, another favorite breeding place for mosquitoes. Be sure to make sure that any bird baths have clean fresh water. Stagnant water is less healthy for the birds and can attract mosquitos.
• Some larger perennials are done blooming around August, which means it is time to start cutting them back to the ground. While some varietals will develop fresh new foliage, others will manage to bloom again before the first frost of the season. Neaten the appearance of long-stemmed plants like Black-Eyed Susans by trimming them back.
• Herbs are best harvested when they are in full swing. For that reason, harvesting herbs should be on your radar this month. Once the herbs have been harvested, dry them for later use. Gather the stems in loose bunches, and hang them upside down in an airy, dry, preferably dark place. This way you can enjoy flavorful herbs for months to come.
(Editor’s Note: Ken Morgan is the owner of Robin’s Nest Floral and Garden Center in Easton, Md.)