“I planted blackberry plants and last year had a tremendous crop. Now most of the canes are dead and I only have a few plants. Do I need to prune the canes and will the plants come back?
Also I have apricot and peach trees, the leaves are curled and the leaves fall off after while. Why is this happening and is there something else I should be doing to stop this?
Thanks for contacting us through Facebook regarding your blackberries, peaches, and apricots.
Blackberries are a perennial fruit that act like a biennial. In other
words, each individual cane that comes up is on a two year life cycle while
its root is always there. The first year, the shoot will come up and only
be vegetative. Depending on the year’s weather, the location they are
growing in, how well they are fertilized, etc., they may be 3-4 feet tall or
as tall as 6-8 feet. The same root may have short canes one year and really
tall ones the next time, so don’t be alarmed. In the fall, the bud/blossom
initials for the following spring/early summer are set.
During the second year of growth, the leaves bud out on the established
canes from the previous summer. The canes bloom and produce fruit. The
remainder of the summer they may start to look a little bit tired and have
leaf drop. It is important to keep the canes after they produces as the
leaves are still photosynthesizing and making food for the roots that will
provide the nutrients to overwinter and grow the following spring. New
canes (we will call it “new shoots II” for this example) will be coming up
The follow summer (third year) the cane will be dead. The canes that are
“new shoots II) are now second year canes and will produce fruits. New
canes (new shoots III) will come up and grow vegetatively. …and so the
The best time to prune your blackberries is in the late fall or early winter
after there has been a dusting of snow. Once the second year canes drop
their leaves at the end of summer, the stem of the cane dies as the plant
goes dormant (first year canes do not die, but go through metabolic changes
to remain alive over winter, like how a tree or shrub would). After the
cane had begun to die and before it gets too cold, numerous types of bugs
can burrow into the dying stems to overwinter. By cutting the canes in late
fall/early winter, it is cold enough that the bugs will be hibernating and
not so cold that you will be out in subzero temperatures or digging through
feet of snow. The canes should be disposed of in the garbage and not a
compost pile to prevent the spread of disease.
As for the apricots and peaches, it sounds like you may have peach leaf curl
on your trees. Peach leaf curl, also known as leaf curl, is a disease
caused by the fungus Taphrina deformans. Peach leaf curl affects the
blossoms, fruit, leaves, and shoots of peaches, apricots, ornamental
flowering peaches, and nectarines, and is one of the most common disease
problems for backyard gardeners growing these trees. The distorted, reddened
foliage that it causes is easily seen in spring. When severe, the disease
can reduce fruit production substantially.
To prevent peach leaf curl, use resistant varieties where possible (Frost,
Indian Free, Muir, and Q-1-8 Peaches, which are only available for
commercial growers). For nonresistant varieties, treat trees with a
fungicide every year after leaves have fallen. In cooler northern locations
leaf fall usually is in late November. In warmer southern locations leaf
fall can be as late as early January. Generally a single early treatment
when the tree is dormant is effective, although in areas of high rainfall or
during a particularly wet winter, it might be advisable to apply a second
spray late in the dormant season, preferably as flower buds begin to swell
but before green leaf tips are first visible.
Historically, the most commonly used fungicides available to home gardeners
have been the fixed copper products. For all copper-containing products, the
active ingredient, copper, is listed as “metallic copper equivalent,” or
MCE, on the label. Various product formulations differ widely in their
metallic copper content. The higher the MCE, the greater the amount of
copper and the more effective the product will be. However, other factors
such as coverage, use of additives such stickers and spreaders, and
frequency and duration of rain, which can wash off the copper, also will
impact product effectiveness. In all cases, the copper is active only when
it is wet, when the copper ions are in solution.
Fixed copper products include tribasic or basic copper sulfate, cupric
hydroxide, and copper oxychloride sulfate (C-O-C-S), but currently only
liquid products containing copper ammonium complex products with 8% MCE
(e.g., Kop R Spray Concentrate [Lilly Miller brands] and Liqui-Cop [Monterey
Lawn and Garden]) are available to consumers. The most effective copper
product, 90% tribasic copper sulfate with a 50% MCE (Microcop) no is longer
available to retail outlets, because the manufacturer withdrew the product
in 2010, although remaining supplies still can be sold.
The copper ammonium complex products can be made more effective by adding 1%
horticultural spray oil to the application mix; the oil also aids in the
control of some aphids, scale insects, and mites. Do not use copper soaps
(copper octanoate), which have a very low percent of copper (0.017% MCE), as
they are not effective for controlling peach leaf curl.
Be aware that repeated annual use of copper products over many seasons can
result in a buildup of copper in the soil, which eventually can become toxic
to soil organisms, and if it moves into waterways, can harm some aquatic
Another option is using a Bordeaux Mixture. Copper sulfate is not a fixed
copper and, when used alone, is less effective than tribasic copper sulfate
or other fixed copper products. However, if copper sulfate is mixed with
hydrated lime to make a Bordeaux mixture, the copper sulfate and calcium in
the lime react together to form a fixed copper product that is effective
against peach leaf curl. Bordeaux mixture is not available for sale; it must
be mixed up just before application, and the ingredients can be very
difficult to find.
In addition, the synthetic fungicide chlorothalonil currently is the only
other noncopper fungicide available for managing peach leaf curl on backyard
trees. Lime sulfur (calcium polysulfide) products no longer are registered
for backyard use.
No matter which option you are using, thorough coverage with any fungicide
is essential to obtain adequate disease control. Trees should be sprayed to
the point of runoff or until they are dripping.
When using pesticides, always read and follow the label for usage, rates,
toxicity, and proper disposal. Proper protective clothing and gear including
goggles should be used when handling any pesticides.
As for physical controls, although symptoms of leaf curl are seen primarily
in spring as new leaves develop, there is little you can do to control the
disease at this time. Some people remove diseased leaves or prune infected
shoots, but this has not been shown to improve control. Normally, diseased
leaves fall off within a few weeks and are replaced by new, healthy leaves,
unless it is rainy.
If a tree is severely affected with peach leaf curl this can stunt its
growth, so consider thinning fruit later in the season. Pruning in fall
prior to applying any fungicides can reduce spore numbers overwintering on
the tree and reduce the amount of fungicide needed. If leaf curl symptoms
occurred on your trees in spring, be sure to treat the following fall and/or
winter to prevent more serious losses the following year.
© Mertie Mae Botanics LLC and Horticulture Talk!, 2011. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Mertie Mae Botanics LLC and Horticulture Talk! with appropriate and specific direction to the original content.