July 17, 2006
 
Gardeners always seem to have an eye on the weather. We tend to track 
the forecasts on a daily basis, watching the temperature and rainfall 
predictions. After all, our plants’ health can be greatly affected by 
weather conditions. This summer we’ve had both wet and dry spells to 
contend with as well as the typical hot spells. This week we will be 
having temperatures well into the 90’s and possibly breaking 100 
degrees, what the weather forecasters call a heat wave. And gardeners 
will try to compensate by giving plants extra water to help them 
through.
 
Just be careful not to over water. Prior to this heat wave rainfall has 
been adequate. Soil that is mulched retains moisture a lot longer than 
bare dirt. Mulched gardens usually do not need watering more frequently 
than once a week even when it’s hot. Many annual and vegetable plants 
will wilt under high temperatures mid-day and then return to normal 
vigor as the sun sets. If your plants are still wilted in the evening 
then they most likely need a drink.
 
Potted plants on the deck or patio will need to be checked daily for 
water during these hot days. Smaller pots and hanging baskets may need 
to be watered twice a day. If the soil in the pot below the first two 
inches is dry, it’s time to water. Watering potted plants every day 
will 
also cause the nutrients in the soil to leach out quickly. Be sure to 
feed container plants regularly with a water-soluble fertilizer. This 
is 
very important for vegetables grown in containers. They can be fed once 
every two weeks during the summer and as often as once a week if you 
water the containers every day.
 
Prior to this heat wave we had high humidity and frequent storms. Some 
annuals, especially in containers, may be past their prime or dead from 
too much water. Trim back plants that have gotten leggy to encourage 
new 
growth. Replace the dead plants with some of the heat loving annuals 
still available at the garden centers. Cosmos, coleus, lantana, 
melampodium, portulaca, vinca, and zinnia all thrive in the heat. And 
the tropical plants like cannas, caladiums, hibiscus and mandevilla all 
add great color to the summer garden. While other annuals and 
perennials 
are beat by the heat, the tropicals will thrive.
 
A long time favorite for summer color in the shade is the coleus. The 
new cultivars of coleus have been bred to tolerate sun as well as 
shade. 
Coleuses are grown for their colorful leaves which range from 
chartreuse, hot pink, deep burgundy and many combinations thereof. 
Remove the flower buds as they develop and pinch the growing tips to 
create full plants. Some of the colorful new coleus varieties to try 
are 
the ‘Sun Lover’s Series’ and the ‘Stained Glass Series’. Besides their 
wide range of colors they come in a variety of leaf sizes, shapes and 
textures.
 
In the vegetable garden beans, cucumbers, squash and melons will put on 
lots of growth in hot weather. Pick beans, cucumbers and squash when 
they are small for the best flavor and texture. Melons and cucumbers do 
best with 1-2 inches of water a week. Keep weeds out of the patch and 
watch for destructive insects. Cucumber beetles, squash bugs and vine 
borers do the most damage on squash, melons and cucumbers. Treat them 
as 
soon as they appear with an insecticide or by handpicking. A second 
planting of beans, summer squash or cucumbers can be sown now if 
needed.
 
Be cautious when applying pesticides and repellents on hot days. When 
the temperature approaches 90 degrees or above an application of either 
type of product can cause leaves and flowers to turn brown and die. 
Wait 
until the evening hours when the temperature drops to apply these 
products.
 
July is the peak month for Japanese beetle activity. Besides eating the 
flowers and leaves of many ornamental plants, the females are laying 
eggs in lawn areas. Now is a good time to apply the season-long grub 
control to prevent lawn damage in late summer. Use a product that lists 
either Merit or Mach II as its active ingredient. Grub control can be 
applied with a spreader and should be watered in after application.
 
Beth Nardone, botanist, is a resident of Hillsborough and is the 
Nursery 
Manager at the Belle Mead Co-Op. Questions and comments can be sent to 
bethtanical@patmedia.net <mailto:bethtanical@patmedia.net> 

<mailto:bethtanical@patmedia.net>