How to Grow Trees
Trees are mostly grown from seeds in two different ways. The first being the most natural way of planting the seed during the fall, the second way is by assisting the germination process of the seed. Germination is usually performed indoors before being transplanted outside.
Germinating Naturally
Trees have always grown the natural way since before man walked the earth so they do not need human intervention to grow at all. When seeds are sown in the winter months, they will start to germinate the following spring. Note that some varieties of seed can take two to three years to germinate. Be sure to know about the species of tree that you are planting as different species are planted at different depths.
Assisted Germination
This method is used to mimic the natural processes that take place outside in nature to help your tree get the best possible start in life. Usually more consistent results can be achieved by assisting the germination process. It is important to read the packet that the seeds came in to find out the best germination process. This is because different seeds need different treatments.
Three main treatments are most commonly used when germinating tree seeds. These are:
Scarification
Cold Stratification
Warm Stratification
Some seeds will need all of these treatments performed while some won’t need any of them. Be sure to check the packet for this.
Scarification
This is the process of breaking the coat of the seed so that moisture can enter to begin the germination process. This is most commonly required with seeds that have very hard shells. Note that many tree seeds do not require this process. For those that do, the easiest way is to soak them in water by pouring it over the seeds and leaving for 8–24 hours. The water should be at room temperature although there are some tree seeds that require hot water.
You can also perform scarification on some seeds by rubbing the seed with sandpaper or a file to break away at the outer coat to allow moisture penetration. Just be careful not to damage the embryo inside of the seed.
Cold Stratification
This is the process of impersonating the natural events that take place during the winter months. It requires exposing the seeds to cold and moist conditions. A common way to achieve this is to soak a few handfuls of peat moss and then squeeze out as much excess water as you can. The moss should be soaked in water but not dripping wet.
Place a layer of moist moss into a plastic sandwich bag. After that, put the seeds on top and then cover with the rest of the peat moss. Close the bag and place in the refrigerator for the required stratification time.
During this time, you should regularly check the seeds for signs of germination. If you see signs then take them out of the refrigerator and plant them as you normally would.
Warm Stratification
As you can guess, warm stratification is used in an attempt to copy the natural events that take place in the summer months. During this period, the seeds are embedded in warm mud or soil. To mimic this process, you should perform the same steps you did for cold stratification but instead of placing in the refrigerator, you place it in an area that is above room temperature, around 70-85 degrees F. Once again, check for signs of early germination; if there is, take out and plant as usual.
Planting Tree Seeds
You should plant the tree seeds into separate containers; the most important part is planting the seeds at the correct depth. You can find out what depth to plant your seeds at by reading the packet they came in. It is typical for tree seeds to be planted a lot shallower than other annual seeds, so always check the correct depth.
Use a good mixture of soil that drains well. A mixture of vermiculite and peat moss makes a good home. Fill the seeds container about ¾ of an inch from the top with the moist prepared soil and always ensure the soil is level.
Small seeds should be sprinkled over the top, while larger seeds will need to be pushed into the soil with your thumb.
Once the seeds are planted water them carefully, you want to keep them moist and not overly wet. It is important to maintain good humidity and moisture levels when germinating the seeds. You can get more humidity by covering the container in a plastic tent with holes in it for air circulation.
You should keep the seed containers in a warm location with dim lighting. Once you notice germination taking place, you must move the seeds to a brighter location.
Germinating seeds can take anything from a few days to several months depending on the conditions and species.