Just think: When you stick those ginkgo biloba seeds into the soil to germinate, you’ll be starting trees that trace their “roots” back 270 million years, making it among the oldest living species on the planet. They live a long time too: there’s one in Asia that is estimated to be 3,000 years old. Ginkgo is a large tree so make sure you have the room for it. Hopefully you do because this tree is a stunner.
Germinating ginkgo biloba seeds, while fun and interesting, requires lots of patience. It won’t be sexually mature until it is 30 years of age. At that time it will produce seeds. Hey, think of it this way: your kids can have the benefit of your labor! If you want to kick start the process, skip the germination and purchase a tree that’s already growing. You can do that here.
What you’ll need to germinate ginkgo biloba seeds
- Latex or rubber gloves
- Peat moss
- Plastic sandwich bag that seals
- 4-inch planting pot
- Coarse sand, coarse sand and perlite or Foxfarm Ocean Foreest Potting Soil
- Household bleach
- Colander or strainer, optional
- Paper towels
Pour some peat moss into a bucket and add a small amount of water. You might want to put on a pair of latex gloves because you need to mix this concoction with your hands. Your aim here is to be able to form a ball of peat that will hold its shape. You will need two handfuls of moist peat so keep adding peat and water until you get there.
Put the two handfuls of the peat into a plastic sandwich bag — the type with a zip-lock closure. Drop five ginkgo seeds into the bag, close it and set it aside in an area that remains around 68 degrees Fahrenheit and it won’t be disturbed. Keep checking it to ensure that the peat remains barely moist and, after one to two months, put the bags in the refrigerator and allow them to remain there for another one to two months. This process is known as “stratification.” Basically, it imitates what the seeds would go through in nature.
When the stratification period is over, remove the seeds from the bag and lightly sand the seed coat — not too much, just enough to allow moisture to penetrate. Drop them into a bowl of water and let them sit for 24 hours.
The next day, fill a 4-inch planting pot with coarse sand, or a mixture of equal parts of coarse sand and perlite. If you’re up for trying something else, I highly recommend Foxfarm Ocean Forest Potting Soil. Run water over whichever medium you’ve chosen until it’s drenched and water drains from the bottom of the pot. Set it aside to drain completely while you sterilize the seeds.
Make a solution of 9 parts of water and 1 part of household bleach and toss the seeds into a bowl of the solution. Allow them to sit in it for about 10 minutes and then remove them and rinse with clear water (a colander comes in handy here). Use paper towels to dry them.
Plant the ginkgo seeds very shallow – just barely cover them with sand. Place the pots in a bright area but out of direct sun, indoors, keep the soil moist but not wet and your ginkgo biloba seeds should germinate within three weeks.
If you prefer, you can plant the seeds outdoors, without stratification, in fall and “good germination should take place in spring,” according to Michael A. Dirr and Charles W. Heuser, Jr. in The Reference Manual of Woody Plant Propagation (the bible for plant propagators and a book I highly recommend.).
If you decide to germinate with stratification, wait until there is absolutely no danger of frost before hardening the seedlings off and then planting in spring.
Germination of fresh seed
If you’ll be gathering seeds from an existing tree instead of purchasing them you’ll need one more piece of equipment, a bucket, so add it to the list above.
The first thing you need to know is that the soft outer layer that surrounds the seed is disgustingly smelly when it decays. Not only that, but touching it may cause dermatitis and even nausea, so wear latex or rubber gloves at all times when working with ginkgo seeds. Even the seed itself may retain traces of a substance that causes the same skin problems as poison oak and ivy.
Fill a bucket with water, submerge the fruit and squeeze the seeds from it. Wash each seed and then dry them. The seeds are now ready to be stratified and planted, as outlined above.
Full disclosure: I get commissions from purchases made through links in this post. I did not receive any of the products I recommend for free — all of the ones I refer you to are those that I purchased and use in my own library and garden.