09/15/2021
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 of ginko biloba seeds 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 ginko biloba seeds from the bag and lightly sand the seed coat — not too much, just enough to allow moisture to pe*****te. 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 ginko biloba 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 blot them dry.
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.