Tips for Germinating Seeds...

'The Bonsai Site'

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A quick look into Tree seeds germination methods:

While not being an exact science, tree seeds germination varies from species to species.  If we are talking about horticulture and compare tree seeds germination to other types of plants, tree seeds are more difficult then other plants. It is not a reason to steer away from tree seeds. Tree seeds are very useful in many ways for horticulturist, including bonsai grower.

First, A very important thing to remember is to maintain the freshness of the tree seeds in order to facilitate proper germination when you will need it. This is why you need to store all of your tree seeds correctly. You can store the purchased or collected tree seeds in a plastic bag without moist element. A humidity rate of maximum 6% is important for seed preservation and excess moisture will make the seeds rot. You can then place your tree seeds in the vegetable drawer of your refrigerator.

Now, lets get to germinating those tree seeds when the time is proper. Timing is important with tree seeds because, even if you can germinate a tree almost anytime of the year, you must follow a certain natural sequence, being the changing of season. You have two (2) germination methods available to you; natural seed germination or forced seed germination.

The natural germination process is the simplest but results vary. First, you will sow your tree seeds outside in autumn. Overwintering the seeds will accomplish all the necessary natural processes tree seeds require to germinate. Next spring, you should have sprouted seeds. However, natural process is hard on the viability of the seeds. If you live in a cold harsh winter region, you will probably have less seedlings in spring then if you use another technique. In mild winter region, the natural technique is also a good choice.

The second method is forced germination. Basically, you are accomplishing the natural germination process artificially. Therefore, you will need to follow the steps listed below. Each tree seeds are different. However most of them require three (3) basic steps. Some may require more while others may require less. These steps are: the scarification, the stratification and sowing.

1 - Scarification

Each seed has a shell around the live inner part. Some are harder than others. The goal of the scarification process is to soften the shell and allow water to reach the inner part of the seed. You will scarify the tree seeds by placing them in water, usually a glass or a bowl, for a period of twenty four (24) to forty eight (48) hours. The norm appears to be the use of warm water. Some tree seeds require boiling water while others require water at room temperature. Normally, the viable seeds will drown after the twenty four (24) hour period while others will float on top. If there are still seeds floating after the forty eight (48) hour period, you can test them by squeezing the tree seed in between a finger and your thumb. If you cannot squash it, then the seed is probably viable and water as not reach the inner part. If you squash it between your finger and thumb , then the seed was empty and you should discard it. Once completed, you are ready to begin the next step ( please note that some seeds require you to proceed directly to the third step).

2 - Cold Stratification

The next step is the cold stratification period. This step is where all the magic of nature occurs. In nature, most of the tree seeds fall from the trees in autumn. Consequently, seeds spend the winter period under colder temperature permitting the chemical in the seeds to develop and trigger the germination process once the ideal temperature is reached in spring. In the forced germination process, you attempt to recreate the winter period magic. In order to accomplish this process, use the following materials:

  • Plastic container
  • Vermiculite
  • Water

You need to fill your plastic container with vermiculite and moisten it. The vermiculite should not be dripping wet but humid. Place your tree seeds in the plastic container and mix it with the moist vermiculite. Once, tree seeds are properly mixed in container, put the lid on it and store the container in your refrigerator for a period varying from thirty (30) to one hundred and twenty (120) days. We suggest that you check your seeds every twenty (20) days in order to prevent rot and allow for proper air circulation. You will also check for germinated tree seeds. If this is the case, take the germinated tree seeds and proceed to the next step. If not, wait the required period and then proceed to the next step.

3 - Sowing

Sowing can be accomplished in the ground or in a pot. You can use any soil suitable for planting and growing as tree seeds are forgiving to which soil they grow in. Make a small opening in the soil (approximately half (1/2) an inch deep), place the tree seed in the opening and cover it with a few millimetres of soil. Keep the soil moist. It is important that soil be moist but not soaking wet. Too much humidity will cause root rot and kill your seedlings.

Extra steps for certain species

If you choose to germinate your tree seeds via the forced germination process, you may be required to follow this extra step. This step takes place prior to the cold stratification. All you have to do is expose the seeds to ambient room temperature for thirty (30) to ninety (90) days. This is called heat stratification and is accomplished by leaving the seeds exposed in a plate on your desk. After you have achieved this step, you resume with cold stratification. This step generally applies to tree seeds that are falling in spring instead of fall.



These are general guidelines to tree seeds germination. While these can serve for almost any tree species, we suggest making some research for your specific tree seeds species before starting your germination process. provides over 60 species of tree seeds suitable for bonsai culture. Tree seeds are available for purchase online in regular and bulk size order. They ship worldwide.