August Gardening To Do List

• Sow seeds of wildflowers and fall veggies
• Aerate, dethatch and fertilize the lawn
• As first frosts threaten, pick mature green tomatoes to ripen in a dark, cool place indoors
• Purchase containerized trees and shrubs to plant now
• Pick herbs to dry for winter soups, stews and baking
• Begin to dig up summer bulbs to store indoors
• Order spring bulbs to force indoors
• Build up weather resistance of trees and shrubs with deep waterings throughout the fall
• Start moving tender plants indoors to acclimatize them or take cuttings
• Spread newly made compost around trees, shrubs and perennials; winter weather will work it into the soil

• Plant hardy Oriental and Asiatic lilies
• Sow seeds of wildflowers, spring-blooming annuals and fall veggies
• Aerate, dethatch and fertilize the lawn
• Start moving tender plants indoors to acclimatize them or take cuttings
• Pick herbs to dry for winter soups, stews and baking
• As first frosts threaten, pick mature green tomatoes to ripen in a dark, cool place indoors
• Purchase containerized trees and shrubs to plant now
• Plan ahead for an extended harvest by building or buying a cold frame
• Begin to dig up summer bulbs to store indoors
• Order spring bulbs to force indoors

• Sow seeds of wildflowers, spring-blooming annuals and fall veggies
• Lift, divide and transplant perennials
• Plant hardy Oriental and Asiatic lilies
• Aerate, dethatch and fertilize the lawn
• Start moving houseplants and other tender plants indoors to acclimatize
• Pick herbs to dry for winter soups, stews and baking
• Order trees and shrubs now for fall planting
• Plan ahead for an extended harvest by building or buying a cold frame
• Blanch tomatoes for freezing and canning by boiling them for just a few minutes and slipping off the skins
• Order spring bulbs to force indoors

Don't Let Blossom End Rot Ruin Your Tomatoes

Keep watching for blossom end rot on tomatoes. The fruits will develop black, canker-like spots at the base. Make sure your garden beds are mulched and that the plants get even moisture. Otherwise, an alternating moist-dry cycle can cause the rot and make the tomatoes inedible.

Reseed Bare Spots in the Lawn

Choose the proper mix of grass seed according to your sunlight conditions. Cultivate the soil lightly and broadcast seed. Water gently and cover with hay or straw. Keep the soil moist until the seeds germinate, and avoid mowing until the plants are 4 to 5 inches tall.

Check for White Grubs

If you have dead patches of grass that pull back like a carpet, check for annual white grubs. A few grubs per square foot are nothing to worry about, but if you find 10 to 12 per square foot you may want to treat the lawn with beneficial nematodes or milky spore, both of which are nontoxic to people and pets. Frequent watering may help grass recover.

Divide Peonies and Daylilies

Peonies and daylilies can be moved or divided at the end of the month. Be sure to water them well beforehand, and dig the plants with a sizeable ball of soil to assure that there are plenty of roots. Replant immediately and water well. Cover with mulch.

Water Fruit Crops Regularly

Water fruit trees deeply to preserve the crop. If apples, plums, and pears don't receive adequate moisture as the fruits are developing the trees may bear small, hard fruits or may abort the crops altogether. Be sure to mulch them well and stop pruning or fertilizing.
• Lift, divide and transplant perennials
• Order peonies for fall planting
• Divide and transplant bearded iris
• Start moving houseplants and other tender plants indoors to acclimatize
• Enjoy a case of the late summer "blues" with a palette of aconitum, caryopteris, fall asters and reblooming iris in your planting schemes
• Blanch tomatoes for freezing and canning by boiling them for just a few minutes and slipping off the skins
• Plant fall-blooming crocus and colchicum for late-season flowering
• Prepare beds for planting bulbs and divide any existing bulbs that might be overcrowded
• Build up weather resistance of trees and shrubs with deep waterings now throughout the fall
• Look forward to something different next spring: try alliums in your bulb garden

Zone 5

• Sow seeds of fall vegetables
• Order peonies for fall planting
• Divide and transplant bearded iris
• Plan perennial beds for fall and winter color with ornamental grasses, fall-blooming bulbs and hardy heaths and heathers
• Harvest vegetables continuously to stretch their season
• Sprinkle compost starter to speed up composting for fall soil building
• Prune summer-blooming shrubs (hydrangea, clethra, caryopteris) after flowers finish
• Plant garlic now for spring harvests
• Look forward to something different next spring: try alliums in your bulb garden
• Enjoy a case of the late summer "blues" with a palette of hardy ageratum, caryopteris, fall asters and reblooming iris in your planting schemes

Plan for Vacation Mowing

If you're going on vacation for more than a week, arrange to have your lawn mowed. The rule of thumb is to remove no more than 1/3 of the growth at each mowing. So, if the grass gets to be 6 inches tall while you're away, you'll want to mow it down to a height of 4 inches, then wait at least 5 days before mowing it again.

Plant Late-Blooming Perennials

Include some late-summer-blooming perennials, such as rudbeckia, sedum, helenium, eupatorium, Russian sage, and goldenrod cultivars, in your garden for an extended bloom season. Many annual flowers will continue blooming into fall with adequate fertilizer and frequent deadheading.

Remove Spent Flowers and Vegetables

Remove spent annual flowers and vegetable plants, compost them, and cover the bare patches with mulch to prevent weeds from taking over. Or, replace them with cool-loving flowers and vegetables. This will keep the garden looking tidy, and help you get a head start on fall cleanup.

Order Peonies

Place orders for peony roots now, in anticipation of planting in September. You'll want to plant the roots about a month before the average first frost date in your area.

Prune Hedges

Prune hollies, boxwoods, and yews now, and they'll have time to develop sturdy new growth before the cold weather hits. If you wait too long, the tender new growth might be damaged by cold.
• Sow seeds of fall veggies and annuals
• Plan perennial beds for fall and winter color with ornamental grasses, fall-blooming bulbs and hardy heaths and heathers
• Divide and transplant bearded iris
• Harvest vegetables continuously to stretch their season
• Sprinkle compost starter to speed up composting for fall soil building
• Prune summer-blooming shrubs (hydrangea, clethra, caryopteris) after flowers finish
• Plant garlic now for spring harvests
• Look forward to something different next spring: try alliums in your bulb garden
• Sow seeds of cool-weather herbs (chives, parsley)
• Enjoy a case of the late summer "blues" with a palette of hardy ageratum, caryopteris, fall asters and reblooming iris in your planting schemes

Zone 7

Collect Rainwater

Summer monsoons have finally arrived, although somewhat sporadically. Use rain gutters to direct water from your roof into collection barrels. Or direct the water to flow to a specific area in the landscape to water plants, such as around trees. If you store rainwater, make sure the container is airtight to prevent mosquitoes from breeding, or place Mosquito Dunks in the water to control them.

Prevent Spider Mites

Along with the blowing winds and dust from summer monsoon storms come the spider mites. These miniscule eight-legged creatures thrive on dusty plants, being especially fond of roses. They are usually noticed by the webbing they leave behind on foliage. Hose off dusty plant foliage regularly to prevent mite populations from gaining the upper hand.

Prune Storm-Damaged Limbs

Strong monsoon winds snap limbs off trees. Carefully prune the damaged branches at a joint where the branch meets the trunk, or where a smaller branch meets a larger branch. This is where the plant's tissue can quickly heal and seal the cut, preventing insects and diseases from entering. Never apply a sealant as this inhibits the plant's own defense system.

Transplant Palm Trees

Palm trees are one of the very few things that thrive when planted in the midst of summer in the low desert. Dig a hole that is as deep as the root ball and twice as wide. Don't amend the backfill with organic material. Soil should be kept consistently moist for six to eight weeks until roots establish. Use a soil probe to ensure that water is soaking deeply through the entire root system.

Watch for Night-Blooming Cactus

Night bloomers, such as Cereus hildmannianus, are showing off their large white or pinkish blooms. The impressive funnel-shaped flowers can grow 5 inches wide and 7 inches long. Peek inside to find insects going about their business.

Divide Virginia Bluebells

A mass of spring-blooming Virginia bluebells is one of the glories of the shaded native plant garden. Even if you only start with a few nursery-propagated plants, they can soon fill a large area if they are divided and replanted every couple of years. Growing best in moist woodland soil, perhaps along a shaded stream, bluebells should be dug up and divided while dormant in summer. They grow best in soil enriched with plenty of compost and bone meal.

Cut Gladiolus for Bouquets

Few flowers are as easy to grow as gladiolus, plus they make almost instant bouquets. When cutting the flower spikes, leave as much foliage as possible because it contributes to the growth of the corm and next year's flowers. Cut spikes on a slant, using a sharp knife or straight-edge razor (with a handle, of course!). Although usually considered too tender to overwinter in our area, glads survive quite well most years, so choose a site where they can remain permanently.

Make Fresh Tomato Salsa

Salsa made fresh, not cooked, is a whole different taste experience. Known as "pico de gallo," or "beak of the rooster," it's fast and easy to make. Combine 2 cups peeled, seeded, and diced tomatoes with 1 cup chopped scallions or onions, 2 tablespoons lime juice, 1 or 2 seeded and minced jalapeno peppers, 1/2 cup chopped fresh cilantro (or flat-leaf parsley), and salt and pepper to taste. Serve with tortilla chips or with grilled fish or chicken.

Order Spring-Blooming Bulbs and Garlic

Bulb-planting time is just around the corner, so study bulb catalogs, then place your order. Choose a variety of bulbs to give you bloom from late winter through late spring. Consider some of the giant alliums, which are real showstoppers in the garden. At the other end of the spectrum are the diminutive early bloomers, like dwarf iris, snowdrops, and crocus. For something unusual in the garden, try some of the fall-blooming crocus, or colchicum. Garlic is easy to grow and should be planted in the fall, too.

Collect and Save Seeds

Seeds can be gathered and planted in late summer and fall from many old-fashioned flowers, such as love-in-a-mist, hollyhocks, dame's rocket, larkspur, and spider flowers. You also can save seed from some herbs, such as dill, fennel, and lovage. Species and open-pollinated varieties will come true from seed, but seed from hybrids won't produce the exact same plants. Clip the browning seedheads and place them upside down in a brown paper bag. Label the bag with the plant's name, close the bag, and place in a warm, dry place. As the seeds ripen, they will fall to the bottom of the bag. Gather them and store in a clean envelope, labeled with the name and date.


• Harvest vegetables continuously to stretch their season
• Sprinkle compost starter to speed up composting for fall soil building
• Prune summer-blooming shrubs (hydrangea, clethra, caryopteris) after flowers finish
• Plant garlic now for spring harvests
• Dig gently to harvest potatoes a few plants at a time
• Look forward to something different next spring: try alliums in your bulb garden
• Sow seeds of cool-weather herbs (chives, parsley, garlic chives, cilantro and dill)
• Plan perennial beds for fall and winter color with ornamental grasses, fall-blooming bulbs and hardy heaths and heathers
• Enjoy fall fragrance by planting autumn clematis (Clematis paniculata), flowering tobacco and annual stock
• Keep cool during summer's dog days with a shade garden embroidered with hostas and hardy ferns
• Color up your bulb garden with fall bloomers (lycoris, fall crocus, colchicum)

Caring for Late-Season Perennials

Late-summer and fall-blooming perennials like Mexican bush sage, Mexican mint marigold, copper canyon daisy, and fall aster should not be sheared after mid July to give them time to grow and set bloom buds on the ends of the new growth. Give them a little boost of fertilizer and keep the soil moist to maintain good health and vigor.

Plant Fall Vegetables

Late July and August is the time to get in that final planting of warm-season veggies, such as summer squash, cucumbers, green beans, chard, and even okra ... but hurry! Potatoes should be planted in mid to late August. I like to start them in 4-inch pots in a bright shady area and then transplant them into the garden in mid to late August. This decreases losses from rot in the hot summer soil. Planting whole smaller potatoes also helps reduce losses from decay.

Rejuvenate Summer-Blooming Shrubs

To keep chaste tree (Vitex), butterfly bush (Buddleia) and crape myrtle (Lagerstroemia) blooming well, trim back spent blooms to prevent the plant from expending energy on seed production. The first two shrubs can get rather loose and unattractive following a good bloom cycle. Trim them back by a third and then provide a little water and fertilizer to stimulate regrowth and another attractive bloom cycle.

Water Next Year's Fruit Now

Most deciduous fruit trees, vines, and bushes are setting fruit buds in mid to late summer for next year's crop. If trees are stressed by drought now, next year's production will be affected. In addition, drought-stressed peaches also will tend to set more "doubles," twin fruits that won't develop normally. Persimmons will drop fruit if they encounter soil moisture stress. Remove vigorous upright shoots emerging from the scaffold limbs and from the base of the trunk to prevent them from shading out the interior portions of the tree.

Pamper New Seeds

To get seeds up and going in this heat, give the seed furrow a deep soaking prior to planting. This "preplant" irrigation is important. Then water the seeds in well after planting. Place a little shade cloth or row cover over the row to slow drying of the soil and reduce soil temperature.
• Color up your bulb garden with fall bloomers (lycoris, fall crocus,colchicum)
• Prepare rose beds for fall planting
• Pick vegetables early in the day while they're crisp
• Plant out vegetable seedlings and sow seed for fall harvests
• Leach out alkaline buildup in the soil with deep waterings and applications of acid plant food
• Dig gently to harvest potatoes, a few plants at a time
• Sow seeds of cool-weather herbs (chives, parsley, garlic chives, cilantro and dill)
• Enjoy fall fragrance by planting autumn clematis (Clematis paniculata), flowering tobacco and annual stock
• Order and refrigerate bulbs that require a winter chill (tulips, crocus, hyacinths)
• Keep cool during summer's dog days with a shade garden embroidered with hostas and hardy ferns

Cut Back Rangy Annuals

It is possible to get another set of blooms from your annual plantings if you cut them back while the weather is still warm. Petunias especially benefit from a mid-season grooming. If you don't want to look at stubs and twigs, simply cut back one third of each plant every week. That way you will always have some flowers to look at while new growth is coming on. Personally, I like to get it all over with at once. Perennial plants such as coreopsis also benefit from an overall haircut.

Fertilize Citrus

Provide citrus trees with a midsummer boost to ensure a crop of flowers. Dibble a citrus-specific fertilizer into the soil around the drip line and water it in well. Keep citrus trees watered during hot weather.

Spread Mulch

Tree-trimming companies are a great source of inexpensive mulch. Call your local tree service to see if they will deliver a load of chippings to your driveway. Mulching reduces weeds, moisture loss, and the spread of fungus disease, plus it just plain looks nice in your garden. It takes a bit of work to spread it around, but it beats bending over to pull weeds.

Fertilize Cymbidiums

Cymbidium orchids need a weekly watering and applications of high-nitrogen fertilizer from now through the end of the month. Follow label directions to a tee!

Harvest Lavender

This is what we have been waiting for! Lavender flowers are ready to harvest and hang. Cut the stems individually near the foliage so that there are no stubs remaining on the plant and the flowers have long stems. Don't cut into the foliage! Tie the flowers in bundles with rubber bands and hang upside down in a dark, dry, warm area. Over the water heater is ideal. Dried lavender can be used to make potpourri or sachets or in arrangements.
• Sow seeds of cool-weather herbs (chives, parsley, garlic chives, cilantro and dill)
• Prepare rose beds for fall planting of containerized roses
• Order sweet pea seedlings now for winter bouquets
• Pick vegetables early in the day while they're crisp
• Plant out vegetable seedlings and sow seed for fall harvests
• Leach out alkaline buildup in the soil with deep waterings and applications of acid plant food
• Enjoy fall fragrance by planting autumn clematis (Clematis paniculata), flowering tobacco and annual stock
• Order and refrigerate bulbs that require a winter chill (tulips, crocus, hyacinths)
• Spray plants with the hose to knock off late-summer pests such as spider mite and whitefly
• Stock up on seed for winter annuals and new perennials

Zone 10

• Prepare rose beds for fall planting of containerized roses
• Order sweet pea seedlings now for winter bouquets
• Plant out vegetable seedlings and sow seed for fall harvests
• Leach out alkaline buildup in the soil with deep waterings and applications of acid plant food
• Spray plants with the hose to knock off late-summer pests such as spider mite and whitefly
• Stock up on seed for winter annuals and new perennials
• Trim and fertilize hanging basket plants to give them a second lease on life
• Order and refrigerate bulbs that require a winter chill (tulips, crocus, hyacinths)

• Prepare rose beds for fall planting of containerized roses
• Order sweet pea seedlings for winter bouquets
• Plant out vegetable seedlings and sow seed for fall harvests
• Purchase and refrigerate bulbs that require a winter chill (tulips, crocus, hyacinths)
• Leach out alkaline buildup in the soil with deep waterings and applications of acid plant food
• Spray plants with the hose to knock off late-summer pests such as spider mite and whitefly
• Sow seeds of cool-weather herbs (chives, parsley, garlic chives, cilantro and dill)
• Prevent chlorosis in citrus trees with three feedings a year
• Trim and fertilize hanging basket plants to give them a second lease on life