I am often asked how we manage to germinate thousands of Japanese maple tree seeds each year because conventional wisdom says that this is considered very difficult to do.

In this article, I’ll reveal the little-known “nursery secrets” we use to ensure near 100% germination rates and debunk the myth that…

Sprouting Japanese Maple Seeds is hard to do… If you have read any standard text or instructions for Sprouting Japanese Maple Seeds and you will usually find virtually identical advice.

Conventional wisdom holds that successful germination of Japanese maple seeds is difficult to do, definitely something for the more advanced gardener. Conventional wisdom also says that the key to successful germination is a combination of soaking the seeds in water followed by “stratification”* (see below).

Soaking the seed is recommended because almost all seed you buy from dealers or unknown sources (such as those you’ll usually find on e-Bay) is dry. The dried seed needs to be rehydrated and then stratified* before it has any chance of germinating.

*Stratification is the scientific term used to describe allowing the seed to experience an extended period of cold for at least 90-120 days, as if the seed had gone through a winter period after falling naturally from the tree.

Even if you’ve tried soaking and sprouting dried Japanese maple seeds, you’ll know that the results are still unpredictable. People tell you that it is difficult, and indeed it is difficult to get a decent level of germination from dry seeds.

We then discover by painful practical experience that the conventional wisdom is correct. It is difficult to germinate most of the Japanese maple tree seeds that you will find for sale. To make up for any lack of success resulting from using this conventional method, you will be advised to leave your seed trays in the ground for another year in the hope that a few more seeds can germinate.

Well good luck! You might get lucky and get a few more seedlings, but it’s more likely that you’ve provided the local mice and other critters with a tasty winter meal!

Conventional wisdom overturned!

Year after year in our nursery we achieve a germination success of 87%, 92%, even 98% in some cases. And we don’t even soak our seed!

Here is the REAL “secret” to achieving a virtual 100% success in germinating Japanese Maple tree seeds…

…Use FRESH new season seeds! Yes, honestly, that’s the most important thing you have to do. DO NOT buy from seed dealers or online eBay sellers who do not care about the success of their seed germination. You will almost certainly get old, dry seeds buying that way.

Having purchased Japanese Maple tree seeds in the past from reputable seed companies and then been unable to germinate them, I decided there had to be a better way.

I stumbled upon the ‘secret’ of using fresh seeds by chance only after finding a ‘rare’ source that offers fresh seeds.

So here’s what you need to do for guaranteed sprouting success…

1. Get fresh new season seeds. Note: The season for fresh seeds is usually from December to March.

2. Store them in a zippered bag.

3. Store them for at least 90-100 days in the refrigerator.

4. Look at the seeds from time to time and make sure they are not drying out. If necessary, add a DROP or two of water, every few weeks, so the seeds don’t dry out.

5. If (and only if) you see mold developing, and as soon as you do, use a fungicide, very sparingly, following the manufacturer’s directions, or apply a weak bleach solution (1 part bleach to 9 parts water)

6. At the end of the cold storage period, the seeds germinate naturally, even in the zip-top bag in the fridge!

7. Transplant seedlings as they germinate, planting the emerging rootlet in a seed compost. We use and recommend using a coco-based growing medium.

We grow many of our seedlings in plastic tubes. These are the same tubes used by the USDA Forest Service. In this way, we minimize additional handling of the seedlings (thus reducing our time/cost and the possibility of damaging the delicate seedlings when replanting).

You should also watch out for late spring frosts. Check out our YouTube video and other online articles on spring frosts and Japanese maples! Your seedlings may germinate in January – February – March and you could face a period of several weeks where new seedlings are at risk of frost damage. Your seedlings should be kept in a frost-free location, but they should also have good light and air movement around them. Keep the seedlings in good light or they will grow long, messy and weak stems.

It is important to remember that seedlings are hybrids. We know the ‘mama’ tree that provided the seeds…

…But we don’t know the ‘dad’ tree whose pollen (thanks to the bee) fertilized the flowers of the ‘mama’ tree. So, just like our children, these seedlings will be similar, but NOT identical to the parents.

The seedlings should exhibit some of the characteristics of the ‘mum’ parent, but will not be identical (a true clone). This means that we CANNOT name seedlings with the same cultivar name as the parent. For example, seedlings of Acer palmatum ‘Bloodgood’ can only be called ‘Seedlings from “Bloodgood” seed’ or Acer palmatum Atropurpureum (if left red).