After several years of growing season drought, we finally had
spring rains. In fact, we had summer rains as well with a record breaking 17
inches in June! While the rains provide a great potential for root recovery, (a
percentage of tree roots die each year that we have drought during the growing
season), too much rain causes fungus problems. Fungus attacks the small tender
leaves of early spring. The symptoms show up later however, when the damage is
done. Fungus symptoms include anthracnose, leaf blotch, powdery mildew and
mottling of the leaves. Mottling of the leaves is a breakdown of the
chlorophyll, the food producing mechanism which goes down in to the root system
to promote root growth and food storage for next year. With less chlorophyll,
there is less chance of root recovery and root growth. In addition, fungus
symptoms can inhibit leaf and flower bud set up for next year.
While the
extreme weather conditions can be very hard on your trees and shrubs, you can
help your plants recover from past drought or fungus symptoms with a liquid
organic fertilizer in the summer or fall. It is important NOT to use a nitrogen
based fertilizer. Nitrogen is not a food, but a catalyst which releases stored
food. Plants, in time of stress, need a liquid organic fertilizer designed to
stimulate root recovery, to create optimal growth conditions and augment the
plant's natural resistance to environmental stress, disease and insects. A
liquid organic fertilizer is a blend of humic acid, enzymes, bacteria, growth
auxins, vitamins and minerals - a real boost for your plants!
While many
of our trees and shrubs show signs of fungus symptoms from too much rain, window
boxes and container plants generally were not seriously affected by the rains.
Continue watering them daily and fertilize once every other week. In contrast to
the liquid organic fertilizer needed for your trees and shrubs, a low nitrogen
fertilizer, 5-10-5 or 10-10-10, is fine for your annuals to keep them
blooming.
Despite June's torrential rains, if summer continues to be hot
and dry, trees should be watered once every 10 days in July and August. A slow
trickle drip with a hose, ideally located at the feeder roots (feeder roots are
in the outer third of the drip edge), for four to six hours is recommended.
Because most city trees are surrounded by pavement however, getting at the
feeder roots is usually not possible. Watering near the exposed trunk may be the
only option and is certainly better than nothing.
Coping with Mother
Nature's fickle character can be stressful on trees and shrubs, but we can keep
our plants thriving with a little tender loving care.