If you haven't already done your August preparation, it might not be too late to check off some of these tasks. By August, the garden is at its peak, but you can lengthen bloom times with a little thoughtful care. Instead of seeing your delphiniums go to seed and your pansies and violas turn into raggedy little plants, you can prepare them for a last blaze of glory before the first frost arrives and ends your gardening activities for the year.
Water August, in many parts of the country, is hot and humid. The weather can be unpredictable too, with thunderstorms, high winds, or punishing rains. Or it can be dry as a bone. The only cure is water, and enough of it, deeply, with a thorough soaking to completely saturate roots and cool the soil. A dilatory spray once a day won't cut it. That just dampens the surface, and may burn leaves and surface roots. Water in the evening as the sun is going down and use the time to commune with your plants. They'll be happier and you'll enjoy the quiet time.
Mulch Beds that are drying too quickly may need a new blanket of good mulch. Adding a rich compost and topping it with a good mulch will both feed your plants and reduce evaporation. Roses are particularly fond of coffee grounds which make an excellent mulch. If you are not into the organic approach, you can apply fertilizer now.
Start autumn annuals from seed Your new mulch and compost are also a great medium for sowing fall annuals like cornflower, annual gypsophila, or phlox. Sow pansies in a shaded seedbed for next spring if you want a wide range of rich color. And since there is no such thing as too many delphinium, now is the time to start them from seed.
Deadhead Another vital task is deadheading your plants and removing dead leaves. This little clean-up project can revitalize plants that are looking a bit ratty. At the same time, if you want to save seed, you can mark seed pods with a bit of bright string.
Stake tall plants If you haven't already staked your dahlias, you might want to do it now. Be careful of the tubers though. Staking earlier (like when you plant) prevents damage to tubers and roots, but if you don't stake, they may wind up with heavy heads laying on the ground...a very sad sight.
Transplant iris If you didn't divide your iris after blooming, now is a good time. Over grown, tightly packed iris may not bloom next spring. Work soil thoroughly and reset young divisions.
Cut back delphinium Once your delphinium have finished blooming, remove spent blossoms, work in compost (or feed), and sit back and enjoy the fall show.
Cut back Lots of plants get leggy by August. Petunias, nasturtium, sweet alyssum can all be stimulated to grow with a little trimming here and there as well as a dose of fresh compost or plant food.
Spray If you are growing tomatoes, you can pick the suckers, put them into a blender with water, and spray your roses with the solution. The solanine in the tomato leaves will discourage blackspot. Make sure your roses have plenty of ventilation and are not crowded. Your tea roses will rest this month. Mulch, compost, or feed, and water deeply. They'll reward you with extra vigor until the weather turns.You can also combat aphids on chrysanthemum and nasturtium with a nicotine solution.
Plant There is no flower more spectacular in color or form than Oriental Poppies. Plant these rich perennials now for a show next summer.