The process of starting new chestnut trees can be broken down to these 3 to
4 steps depending if the tree is to be grafted or not.
1. Getting the chestnut to start germinating - extending the tap root out
of the nut
2. Placing the germinating chestnut seed in a container of soil where the
seed will complete the germinating and put up top growth of the new tree
3. When the seedling is big enough, the seedling will be transplanted into
4. If the seedling is to be grafted, then the following summer the seedling
will be grafted with scion wood from a compatible cultivar
For a simple 3 step process, it's a wonder why more nurseries are not
propagating chestnut trees. In 2009 Fowler Nurseries sold its last chestnut
trees. A short discussion with one of the managers brought out these issues
with propagating chestnut trees commercially:
1. Low percentage of seeds germinate
2. There is a high percentage of graft failures
3. The price the chestnut tree will bring is low compared to the inputs
4. Chestnut trees do not grow consistently from year to year
This list does not even include insects, drought, late frosts, wet soils,
gophers, deer, rabbits, and many more creatures that munch on chestnut trees.
Knowing all this and still proceeding with propagating chestnut trees is
likely going to be a money loosing endeavor, go right ahead! Let's go at it
and propagate us some chestnut trees.
The first order of business is to give up some money to buy chestnuts for
seed and some moss (the type of moss put into hanging baskets). The moss can
be purchased from a garden or nursery store.
Be careful, buying chestnuts from grocery stores, many times the
chestnuts will have had a hot water bath. The hot water bath kills chestnut
seeds. The best way to purchase chestnuts for seed is directly from a chestnut
grower. The nuts will not be any cheaper but they will be fresh and
unprocessed and hopefully from a known chestnut cultivar. Be sure to purchase
twice the amount of chestnuts you think you will need. This is to compensate
for the low germination rates of chestnuts.
You now have the chestnuts for seed in your hands. Now you need to get the
rest of the materials needed to start the germination process. Zip lock
storage bags work well for storing chestnuts during the stratification period.
Don't put more than 25 chestnuts in a 1 gallon zip lock bag. The zip lock
storage bags have to have holes punched into them to allow the chestnuts to
breath during the stratification period.
Next take the moss, when purchased from a store it is usually dry and must be
moistened. Place the moss in a bucket if water for about 5 minutes. Then
drain out all the water. As you remove the moss from the bucket for placing
into the zip lock bag, squeeze the moss to remove excess water. The chestnuts
must be loosely packed in the moss. The moss has to be damp to help the keep
the chestnuts moist. If the chestnuts dry out during the stratification
period, the chestnuts will never germinate. This is the only time in the
life of a chestnut that drought is a killer. When packing the chestnuts in
the zip lock bags, pad the chestnuts with the moistened moss so the chestnuts
do not touch each other.
The stratification process takes months. The storage temperature during the
stratification period is very important. Most people put the zip lock bags
filled with the chestnuts in a refrigerator. The chestnuts should never get
colder than 28 degrees F. The chestnuts should not be stored at room
temperature for more than a few hours at a time. The best temperature is
between 32 and 38 degrees F. The chestnuts will remain stored in this cool
place until February.
Planting Seeds in Growing Pots Indoors/Greenhouse
Fill the 1 gal growing pots with the sterilized potting soil leaving about 1
inch from the top of the pot. Only use chestnuts showing signs of germinating
in this process from step 15 above. Place one germinating chestnut in the
center of the pot on top of the soil. Now leaving about 1 inch spacing from
the center chestnut place 5 germinating chestnuts evenly spaced around the
pot in a circle. Place about 1 inch of sterilized potting soil on top of the
chestnuts. Slightly compress the soil with your hand. This helps prevent
moisture loss. Place the entire pot inside a small size clear trash bag. Tie
the bag shut with a wire tie. This keeps the soil from loosing moisture.
Between the time you seal the bag to the time the chestnut tree emerges from
the soil the bag will remain sealed.
Twice a week check the pots for emerging chestnut trees. When the chestnut
trees start emerging, remove tie on the plastic bag. Keep the bag around the
pot. When you water the seedling trees the plastic bag helps keep the water
from running all over the floor. The seedlings need sunlight to grow. Place
the seedlings in the pots near a window that gets full sunlight. The seedlings
will remain in these pots until there is no further chance of frost (usually
mid May). In May the seedlings will be removed from the pots and transplanted
into the field/yard.
Directly Planting of Chestnut Seeds
Farmers use the term "direct planting" to mean the seeds are placed directly
in the ground outside. Direct planting of chestnut seeds has its hazards. The
two greatest hazards are rodents and freezing. If chestnut seeds freeze they
will not germinate (this is a fact and not just a possibility). If you live in
an area where the ground freezes then do not plant the chestnut seeds until
the ground has warmed enough to prevent freezing. Rodents love chestnuts.
There are only two methods known to work well to keep rodents out of chestnut
seed beds. The first is to use a ground sounder used to keep moles at bay.
These sounders are placed in the soil near or in the chestnut seed bed. The
sounders emit a 300 hertz signal about every 30 seconds. The other method
uses wire mesh in the ground around the seed bed and on top of the seed bed.
The wire mesh has to be buried at least 12 inches to keep the rodents out.
This takes more labor but does the best keeping the hungry ones out.
When direct seeding chestnuts, remove about 1 to 2 inches of soil where you
want to plant the seeds. Place seeds no closer than 4 inches apart in the rows
and the rows have to be 18 inches apart. In addition, the seeds can be covered
with peat moss to keep the chestnuts moist. Once the seed have been placed,
put the removed soil back on top of the chestnut seeds. Do not let the soil
dry out. If the seeds are in dry soil the seeds will also dry out killing
them. Keep the seed bed weed free at all times. It will take 3 to 6 weeks for
the seeds to complete the germinating process and start emerging. Soil
temperatures must be above 55 degrees F for the chestnuts seeds to continue
the germinating process. Temperatures below this will cause the chestnut seed
to take longer to emerge from the soil. Direct seeded seedlings will be
transplanted the following spring between mid March and mid April depending
on soil conditions.
Transplanting Chestnut Seedlings
Finding the right location for planting chestnuts consists of finding sunlight
and well drained soil. Do not plant chestnut trees it clay or heavy soil, they
will die. Chestnut trees will grow in partial shade but they grow slow and
will not produce lots of chestnuts. Chestnut trees should be placed no closer
than 25 feet apart with 30 to 40 feet being best.
Chestnut seedlings started pots with potting soil can be transplanted any time
after the last frost. If a chestnut seedling gets frostbit, it has a 50/50
chance of surviving. It will get set back for weeks if it does survive, so it
is better not to chance placing the seedlings out too early. When transplanting
dig the hole about twice the size of the container the seedling is being
removed from. This gives space around the seedling with soft soil to extend
its roots into. When separating the seedling from other seedlings in the pot
be careful of damaging the roots and keep as much soil as you can with the
seedling. Place the seedling with the potting soil around the roots into the
hole you dug. Fill the hole around the seedling. Do not compress the soil
other than with your hands. The newly transplanted seedling has to be watered
right away. This causes the soil to settle around the roots. This is a very
important step and can not be left even if it is raining. If the soil is
already water saturated then the seedling will die in a few days. A better
choice would be to plant the chestnut seedling in well drained moist soil. Use
water soluble fertilizer such as "Miracle Grow" when watering chestnut
seedlings. Never over water chestnut trees/seedlings as this could kill them.
If the soil contains too much water for chestnut trees to grow, it makes a
squishing sound under foot steps.
Return to Chestnut Guide Index
Photo 1: Chestnut seedling with frost damage has new buds