Bearded irises are planted as rhizomes in August and their tops should be exposed when planted. Planting the rhizomes in August will let the iris become established before the winter and bloom next spring.
In order to calculate your fall garden planting date, determine the frost date and count back the number of days to maturity plus 18 days for harvest of the crop. If snap beans mature in 55 days and your frost date is November 15, you should plant on or before September 3.
Order fall bulbs for planting.
Sow seeds of poppies and bachelor’s buttons where you want their blooms next spring.
Order spring-flowering bulbs for fall planting. Store in a cool, dry place. Plant in late fall and early winter.
Plant a fall crop of peas. The roots of peas "fix" nitrogen into the soil for next spring planting. Remember, when planting peas for fall, plant them almost twice as deep as spring-planted peas. This will help keep the seeds cool and also from drying out before they germinate.
Plant annual flower/ornamental plants such as blue daze, celosias and zinnia.
Prepare soil for September through October plantings of Bonnie cool-season crops. Apply fertilizer and compost so rains will settle the rows and make it easier to get plants started when they are planted.
Sow seeds for biennials such as hollyhocks or foxgloves or transplant seedlings for blooms next year.
Plant spring wildflowers. They must germinate in late summer or early fall, develop good root systems and be ready to grow in spring when the weather warms. Plant seed in well-prepared soil, one-half inch deep and water thoroughly.
Don’t fertilize woody plants now. It stimulates green growth that may not have time to harden off before winter.
Have soil tested for fall fertilization requirements if it has been 3 years or more since the last analysis.
Apply a complete fertilizer to all species of warm-season turf grasses. For average lawns, this should have a ratio of high nitrogen (first number of the analysis), low phosphorus (second number) and medium-to-high potassium (third number). If you can’t find this, apply a 13-13-13 or triple 8 fertilizers so that some N, P and K nutrients are all included. Controlled release formulations are best at this time.
Cut back lavender once it has finished flowering.
Keep deadheading flowers as they fade; not only will the plants look better but, if they’re allowed to produce and shed their seeds, they’re more likely to stop producing new blooms.
Pinch back tomato plants for a higher yield.
Prune hybrid roses late in the month.
Prune out and destroy blackberry canes that bore fruit this year. They will not produce fruit again and could harbor insects or disease.
Take cuttings of geraniums.
For prize-winning winter squash and pumpkins, pinch off any female flowers and young fruit that develop from now on.
Now’s the time to do one last shearing of the evergreen hedges. Growth will be tapering off soon, and they probably won’t need attention again until next spring.
Water perennials weekly and deeply.
Anytime we go for four to six weeks without at least an inch of rain, established trees need water. Trees less than 2 years in the ground need water every one to two weeks, depending on the soil, weather and species of tree. Place a bubbler, a small sprinkler or a soaker hose at the dripline of the tree (the area on the ground - a circle - corresponding to the furthest reaches of the branches above), and water for 30-60 minutes or more with a low flow of water.
Because August is usually the hottest month of the year, watering is a top priority in lawn care.
If your grass is dry, do not mow until you have watered or until it rains. Mowing a dry lawn will further stress the turf and expose it to the drying effects of the wind and sun.
Check water in hanging baskets and container plants every day in hot weather.
Conserve water. Water early in the morning. In addition, the more water on the leaves, the greater the chances of fungal problems on the leaves. Water on the leaves while the sun is out can cause burning of the foliage.
Consider investing in soaker hoses and/or a drip system. These watering systems put the water right where it’s needed (in the soil and next to the plant) rather than wasting the water into the air. Of course, this also saves on the water bill and, again, reduces the chances of diseases on the plants. While soaker hoses are easier to install in the garden or landscape, a well-designed drip system can last much longer.
Houseplants will need to be watered more often this month, especially if they’re in a sunny window.
If water is scarce, consider letting your lawn go dormant, and reduce watering to once a month. It may look a little scrappy, but that glowing green hue will return with fall rains.
If you’re keeping a green lawn, give it an inch of water once a week or slightly more often.
Make a frequent check of flowers and vegetables for their watering needs. Generally, you’ll want to give them about an inch of water each week; deep, less frequent watering is better for them than frequent surface watering.
Stop watering potted amaryllis bulbs; store them in a dark, dry spot for several weeks, then bring them out again to initiate winter bloom.
To check on water levels, trowel into the soil and look for moisture to a depth of three or four inches, or deep enough to ensure that water is reaching roots.
Always read the label before using chemical pest controls.
Kill or remove poison ivy from your property before it goes to seed.
At first notice of aphids, hose-blast them off of leaves or spray them with an insecticidal soap.
Extra watering and hot weather make August a red-letter month for weeds. Expect weeds to germinate and drop their seeds faster; pull them out as soon as they pop up.
Scout for pest problems and treat as needed. August is prime time for bagworms on evergreens, budworms on annual flowers, a second generation of scale on euonymus, webworms on fruit trees, spider mites on evergreens, scale on magnolia and lace bugs on azaleas.
Slugs will tend to be more abundant now due to extra watering; plant saucers of stale beer or yeast water around the garden, especially around mulched areas (a favorite slug hiding place) and near tender greens.
Solarize empty beds to kill weed seeds and disease pathogens: Water the soil thoroughly, then seal it with clear plastic for 6-8 weeks. Weigh the edges of the plastic down with soil, bricks or landscape timbers.
Spray water on the top and undersides of zucchini foliage, early in the mornings, to control spider mites and aphids.
To avoid giving pests a free lunch, pick fruits and vegetables as soon as they’re ripe.
Over 3,000 children, 14 or under, are among approximately 80,000 people treated in U.S. hospital emergency departments every year for lawn mower injuries. Here are some safety tips from the American Academy of Pediatrics:
Don’t allow children under age 12 to operate a push mower or those under 16 to drive a riding mower.
When children and adolescents are old enough to use mowers, teach them safety steps such as wearing goggles and sturdy shoes.
Do not allow children to ride on mowers as passengers.
Keep children off the lawn while mowing.
Pick up potential flying objects such as stones and toys before you start mowing.
Do not pull a mower backward or ride it in reverse unless absolutely necessary. If you do mow backwards, carefully look for children behind you.
Raise the cutting height on your mower to keep grass longer, conserving water and helping roots stay cool.
Gather herbs and flowers for drying and preserving. The best time to gather herbs for drying is during the mid-morning hours, just after the dew has dried off the herbs, but before the sun causes them to wilt. Cut the herbs in clusters with the stems attached.
Add a light layer of mulch around young plants to help their roots retain moisture.
Be especially vigilant about ventilation and watering needs in the greenhouse this month.
Harvest watermelon when the underside ground spot turns from whitish to creamy yellow; the tendril closest to the melon turns brown and shrivels; the rind loses its gloss and looks dull; and the melon produces a dull thud rather than a ringing sound when thumped.
Spade or till soil for fall bulb planting; add a moderate amount of fertilizer.
Keep your cutting tools sharpened and in good repair.
Establish a new compost pile to accommodate the fall leaf accumulation.
Wear safety goggles when using all portable power tools such as trimmers, blowers, chain saws, etc.
Before you head out for vacation, move houseplants out of direct sunlight, especially those in south-facing windows.
It’s apple-pickin’ time! Early apples should be ready to pick this month.
Homegrown dill is delicious, easy to grow and harvest. You want to harvest almost mature dill seeds, not the green ones or the completely dry ones. The green ones won’t have the flavor you are looking for and the dry ones will have already dropped most of their seeds.
If any patches of annual flowers have petered out in the heat or been eaten by bugs or animals, hide the bare spot by moving a flower pot over the space.
Mulch, mulch, mulch! If you haven’t done so already, be sure all bare soil is covered with mulch, or compost with mulch on top. Avoid putting mulch or compost onto plant stems. Use about three inches total wherever possible.
Pick beans, tomatoes, peppers and squash often to encourage more production.
Take photos and make notes for next year’s landscape.