How do I prevent the seeds on my Japanese Maple from falling off?

Question

I have a 6 ft tall 'Bloodgood' Japanese Maple in my yard. It gets a lot of afternoon Californian sun, but the leaves are a nice color and are healthy.

I wanted to collect some seeds this fall (to try to grow some unique seedlings and the such) and was pleased earlier this year that there were multiple bundles of maple seeds growing.

Come this month, they've all dried up—died immature—and fallen off the tree. Is there any way that next year I can save some seeds and prevent them from falling off prematurely? Or should I just wait for the tree to get older, as it's not very old yet?

Answer 1

There are many reasons plants might not successfully reproduce in a season, and there's really no way of preventing seeds from prematurely aborting unless you find out exactly why it happened, and even then it could still be out of your control (i.e. if it's down to the tree's ability to breed successfully). Has it produced viable-looking seed in the past?

Answer 2

Plantpropagation.com is a commercially sponsored site, but they have this information for Japanese Maple:

Most Japanese Maple seeds ripen in the fall. Watch the tree and wait for the seeds to turn brown. The seeds are ready to be harvested when they are brown and can be easily removed from the tree. The seeds are attached to a wing, it's best to break the wing off before storing or planting the seeds.

Japanese Maple seeds have a very hard outer coating as do many ornamental plants. Under natural conditions the seeds would have to be on the ground for almost two years before they would germinate. All that happens the first winter is the moisture softens the hard outer shell, and the second winter germination is beginning to take place. In order for all of this to happen in the proper sequence so the seedlings actually sprout at a time of the year when freezing temperatures or hot summer sun doesn't kill them, takes a tremendous amount of luck. You can improve the odds by controlling some of these conditions, and shorten the cycle.

Once you have picked the seeds and removed the wing just place them in a paper bag and store them in a cool dry place until you are ready for them. You don't want to plant your seeds out in the spring until the danger of frost has past, here in the north May 15th is a safe bet. If May 15th is your target date you should count backwards on the calendar 100 days. That will take you to about February 5th if my math is correct.

On or about the 100th day prior to your target planting date, take the seeds and place them in a Styrofoam cup or other container that will withstand some hot water. Draw warm to hot water from your kitchen faucet and pour it over the seeds. Most of the seeds will float, just leave them in the water overnight as the water cools down. 24 hours later most of the seeds will have settled to the bottom of the cup, drain off the water. Place the seeds in a plastic bag with a mixture of sand and peat or other suitable mix. Even light potting soil will work. The peat or soil should be moist, but not soaking wet. Poke some holes in the bag so there is some air circulation, and place the bag in your refrigerator for a period of 100 days.