University of Vermont Extension 
Department of Plant and Soil Science

Summer News Article

Charlie Nardozzi, Horticulturist
Vermont Botanical Garden, and
Dr. Leonard Perry, Extension Professor
University of Vermont

Staking flower and tomato stems, getting rid of mosquito habitats, and proper harvesting of herbs, are some of the gardening activities for this month.

Support single stems, such as delphiniums, with stakes.  I like to use green plastic-coated metal ones, or iron rods, as these don't rot as wood does.  Use soft twine, foam cord just for this purpose, even old panty hose, to tie stems to stakes.  These avoid cutting into and harming the soft stem tissues.

Use cages, stakes, or trellises to keep tomato plants upright. Tie plant stems to their supports with soft materials as for single flower stems.  Unlike most flowers though, fruit-laden tomato plants are heavy, so supports must be sturdy. If you're using cages, anchor them with a stake.

Examine your yard for areas with standing water, such as old containers or upturned garbage can lids, and dump them. Mosquitoes breed in these types of places, so by removing them you'll get a head start on controlling the pests. Use "mosquito dunks" in ponds. These disks contain a specific strain of Bt (Bacillus thuringiensis) that controls the mosquito larvae. Follow label instructions.

The best time to harvest most herbs is just before they flower. At this time the leaves have the highest concentration of essential oils. Some herbs, such as basil, will respond by putting out a new flush of growth. Rather than picking off individual leaves, harvest entire stems right back to a set of leaves.

Continue making succession plantings of vegetables to ensure a harvest well into autumn. If possible, plant cool-season crops like broccoli where they'll get a little shade from the hot afternoon sun. Plant another row of bush beans for late summer harvest.

If you'll be away from home for more than a few days, take steps to keep container plants healthy. If possible, have a neighbor water plants daily or as needed. If that's not an option, move containers to a shady location and water plants thoroughly before you go. Group small containers together and set in a shallow basin filled with an inch or two of water. Self-watering containers are a good choice if you travel frequently during the summer.

Birds love blueberries as much as we do, so protect bushes with netting. Rather than draping the netting over the bush - birds will be able to reach the berries - use stakes to suspend the netting over the shrub. Secure the netting to the ground to prevent birds from sneaking in.

Check your flowers, at least weekly, for pests and diseases.  Some cultivars (cultivated varieties) of flowers such as garden phlox and zinnias may begin getting a whitish covering on the leaves.  This is likely powdery mildew disease, and can be kept in check with sprays or cultural techniques.  Diseases in most flowers can be lessened by avoiding overhead watering, especially late in the day when leaves remain wet through the night.  Improved air circulation, such as from thinning out stems, also may help reduce diseases.

Other July gardening activities include removing watersprouts or suckers (those vigorous new stems from the base) on grafted roses, crabapples and apples; keeping compost turned regularly, to speed the process; drinking plenty of water on hot days while gardening; and taking a day to attend a garden tour or to visit other gardens.

Return to Perry's Perennial Pages, Articles