Chapter 2: Starting Chestnut Trees from Seeds

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 the field

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.

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