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Apricots
have been a problem fruit to grow in Texas for many
years. Although the fruit can be grown in most areas of
Texas the trees do not produce every year and may only
produce a crop of fruit in 2 out of every 5 years. That
is not a good situation for most people interested in
growing the fruit. It is disappointing to have the trees
bloom and then see the blooms or young fruit destroyed
by one of our late freezes. The main reason for
inconsistent cropping is that apricots are normally one
of the first fruit trees to bloom in the spring.
There are things you can do to make apricots bear more
consistently. The first is variety selection. By
selecting a variety that blooms later than most apricots
or has a long blooming season, as well as the varieties
that have hardy blooms, you can get past many of our
late frost problems.
To determine variety
selection we need to examine the origin of our domestic
apricots. Apricots originated in an area from central
Asia to Manchuria. The central Asian apricot group is
the ancestor of our present European/American apricot
varieties. There is great diversity in the central Asian
group but the European/American group of apricot
varieties has very little genetic diversity. In other
words, our present American apricot varieties are very
much alike in their characteristics: large, good
shipping fruit of fair taste with an early bloom time.
The central Asian apricots are small, very sweet tasting
fruit on trees that bloom very late (when compared to
American apricots). This late blooming characteristic is
what we are interested in when breeding apricots for the
future.
An apricot breeding program in New Jersey
used a central Asian apricot variety called 'zard'
crossed with a French variety to develop an apricot
variety called 'jerseycot' that blooms nearly two weeks
later than most American apricot varieties. The 'jerseycot'
variety is not available commercially but budwood can be
obtained for grafting.
The USDA sent a fruit
exploration team into northern Pakistan to the Hunza
valley to procure some of the famous apricot varieties
growing there. The Hunza people eat as their main diet:
dried apricots, apricot seed oil, roasted apricot
kernels and millet. It must be mentioned that our
American apricots have kernels that are poisonous,
whereas the Hunza apricot kernels are sweet and edible
when roasted. The people in the Hunza valley live longer
than most people in the world, and cancer is nearly
unknown. There must be something about their food that
contributes to their health.
With seed and
budwood in hand, the team brought the Hunza varieties
back to the USDA research station in California. Now
they are crossing the Hunza apricots with our American
apricots with the hope for later blooming apricots with
larger, sweeter, good shipping fruit. Dr. Craig
Ledbetter is heading up this effort with the USDA. He
says that the Hunza apricots hold promise but the fact
that the fruits are small makes them unsuitable for
commercial production unless the cross breeding program
is able to develop larger fruit.
The Canadian
agricultural research station at Harrow, Ontario, Canada
developed several later blooming apricot varieties, with
the best all-around being 'harglow.' It has good sized
fruit and it truly blooms later than most apricots. It
is available through mail-order from several nurseries.
The South Haven Experiment station in Michigan some
years ago developed an apricot variety that, although
not a very late blooming apricot, has blooms that can
stand more frost than ordinary apricots. It is called 'chinese'
and should be considered a good variety for all areas.
It has clingstone fruit which means that it is not a
good commercial prospect, but for the home grower it can
be a good one.
The research station at Prosser,
Washington, developed a variety called 'tomcot' that
although it does not bloom late, it blooms over nearly
three weeks which means that if the first blooms are
bitten by a late frost the later blooms have a good
chance of producing fruit. The fruit matures early and
is of good size and flavor. It is considered a
commercial apricot because of its large size and good
shipping qualities.
Varieties developed from
unknown parents (seedlings) in our state are another
good source of later blooming or bloom hardy apricot
varieties. Two varieties that fall into this category
are 'tisdale,' sold by Womack Nursery in De Leon, Texas,
and 'bryan,' a variety sold by several Texas nurseries.
Both have more consistent production records in Texas
than most apricot varieties available. They do bloom a
little later and are considered mid-season bloomers.
The second thing that will help prevent frost damage
is environmental in nature. Years ago, people might
drive by a fruit orchard and see fruit trees with their
trunks painted white and think that sure makes a nice
looking orchard. Well, the painting of the trunks with
white latex paint diluted 50-50 with water is more than
a nice looking feature to an orchard. By using regular
white latex (not oil based paint) and mixing it with an
equal amount of water and then applying it using a
painting glove (sold at many paint stores) or sprayer
you can do two things: 1. keep the trees cooler,
resulting in a later bloom time for your apricots, and
2. help reduce insect problems from insects that borrow
into the bark or crawl up the trunk from the ground.
Keeping the trees cooler than normal will help delay
any apricot's bloom time. You can put down a layer of
compost or mulch under the trees and keep the soil
cooler as another method of delaying bloom. Just do not
put it directly up against the trunk of the tree.
Planting trees on a slope so that frost can "drain
away" downhill also helps produce apricot crops in areas
prone to late frost. In commercial orchards sometimes
sprinklers are used to spray trees with water when a
frost is expected, but for the home grower that is
usually not an option.
Something must be said
here about chilling hours for apricots (that's the
amount of hours in winter below 45øF). Many of the
apricot varieties need about 700 hours of winter
chilling, to produce a full bloom in the spring. At
least 2/3 of Texas has 700 hours of chilling so most of
us do not have to worry too much about this. However,
for the people in the southern part of the state there
are low-chilling varieties that should be considered.
The Gold Kist variety has a very low chilling
requirement of 300 hours and can be planted in the
southern part of the state with a good chance for
production. 'Katy,' a California variety with a 400 hour
chilling requirement, is also a good candidate for the
same area.
Apricot culture is not too much
different from most stone fruit (peaches, plums,
cherries etc.) A good deep loam type soil is best, but
most fertile soils will suffice. A dry climate is best
if the trees can be watered in periods with low
rainfall. Apricots are the most drought tolerant of all
the stone fruit, especially on apricot rootstocks (most
apricots are grafted on peach rootstocks). Apricot trees
are very long-lived trees, much longer than peaches.
There are apricot trees in Texas still producing fruit
at 40 to 50 years of age.
Apricots like a sunny
location along with pruning that allows the sun to
penetrate into the tree. They do not require as much
pruning as peaches but the open center type of pruning
is best for apricots because the more sun the fruits get
the nicer they will appear. Prune any limbs that overlap
and remove any limbs that start too close to the ground.
You must be careful not to prune too much since apricots
bear fruit on fruit spurs that are 2 years old or older.
So if you prune too much you will not have a good crop
the next year.
Pests can be a problem with
apricots but not as much as with many other stone fruit.
The plum curculio is a major pest that can cause much
ruined fruit. It can be held in check by spraying at
petal fall (the time when the bloom petals start to fall
off) along with one to two additional sprays at 10 days
to 2 week intervals. Check with your county agent or
local garden center about what chemicals to use. There
are other insects that cause problems but the plum
curculio is the worst insect problem in our state.
Watch for birds pecking the fruit. If you get one of
the earlier ripening varieties the chances of bird
damage will be less because the early fruit just do not
get noticed as much as fruit maturing later in the
season. You can use bird netting, but usually you have a
large enough crop that letting the birds have a few is
not a problem.
One thing that has just recently
been discovered is that apricots need a good supply of
zinc. Dr. Ledbetter of the USDA believes that a fall
application of zinc causes the flower buds to develop
better for blooming the next spring. You can use zinc
sulfate applied and worked into the soil, and there are
foliar sprays that contain zinc which can be applied.
You may be aware that pecans have this same zinc
problem. Lack of trace elements in the soil can be the
source of problems with trees that fail to bloom and
fruit. A soil test is best if you have trees that are
old enough to set fruit but fail to bloom. Any county
agent in Texas can supply you with materials for a soil
test through the Texas A&M extension service at a very
small charge. I have been asked by a number of people
why their apricots have failed to bloom and set fruit.
The lack of some of the trace elements — especially zinc
— may be the answer.
Richard Ashton is the
author of several books on fruit growing. The
Incredible Pomegranate - Plant and Fruit, Jujube - The
Chinese Date and his soon to be published book
Sweet Cherries for Southern Orchards are available
from Third Millennium Publishing at
www.3mpub.com/ashton or they can be purchased
through the Texas Gardener bookstore.
| SOURCES |
I have
mentioned several apricot varieties that seem to
have better chances of producing reliable crops
in Texas. Here are a few places to get them:
Womack Nursery in De Leon, Texas, (254)
893-6497 has the Tisdale variety, which
is a good all-around variety. They also sell
Peggy, a variety that I would not recommend
for all of Texas but is good for the North Texas
area. These are both Texas developed seedling
varieties.
The Tomcot variety can
be purchased from Van Well Nursery in Wenatchee,
Washington,
www.vanwell.net or (509) 886-8189, which
ships trees bareroot in the early spring. They
have started a program where you can purchase
just one tree (although they are a wholesale
nursery). It is advisable to plant another
variety with the Tomcot variety for
better production, although it will produce if
planted alone.
Bay Laurel Nursery of
Atascadero, California, sells several of the
varieties that I have mentioned by mail order,
including the low-chill varieties. They are on
the Web at
www.baylaurelnursery.com or by phone at
(805) 466-3406.
You can get scionwood for
grafting of the Jerseycot variety by contacting
the USDA-ARS and asking for Accession DPRU1051 —
'jerseycot.' They are at:
www.ars.usda.gov/Main/docs.htm?docid=13394
on the Internet or you can call them at (530)
752-7009. The scionwood is free but must be
ordered before December 1 of each year. |
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