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Resources for Growing trees in Ottawa

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Back to the web version Resources for Growing trees in Ottawa This page is about growing trees from seed: where to buy seeds or seedlings, how and when to gather seeds and how to grow them.
Compiled by Jeff Blackadar. I would be interested to know if these tips helped you grow trees or if there is additional information you'd like to see here.

Growing trees from seed
Growing trees from seed is a highly rewarding experience. Even if you grow many trees from seed, you'll find your friends and neighbors will be more than willing to take your excess seedlings off your hands.

Tree Seedlings

General References

Growing specific trees from seed on a small scale
 (This area is being added to)

White Cedar Thuja occidentalis
White Cedar is commonly used in hedges in Ottawa and is readily found growing naturally. These trees are easy to grow from seed. Collect seeds from late August - Mid October; look for trees with an abundance of cones where the cones have matured and changed from yellow/green to brown in colour. Extraction of the seeds is very easy, simply leave the cones on a piece of paper in a dry area for a few days. After a while the cones will open and the small flake-like seeds will fall out. Get rid of the cone debris and place the seeds in a sandwich bag which is air tight, put the bag of seeds in a fridge until you're ready to plant them.

If you are planning to grow the seeds indoors, start seedlings in a mini-greenhouse. The seedlings will need light, so place the mini greenhouse by a window or use fluorescent lights (12 hour / day timer will work fine). You can grow the seeds on a seed starting medium (which you can get at any garden centre) or using "Jiffy" (compressed peat) pellets. I've used Jiffy pellets to start these seeds with good results; I just presoak the pellets in water and sprinkle the seeds on top. After a few weeks the seedlings will be growing. If you have more than 2 seedlings per jiffy pellet, select the best and thin out the rest. Eventually you'll want to thin down to 1 seedling per pellet; it's too difficult to separate the seedlings later if you don't thin them. Keep the lid on the mini greenhouse and water the seedlings occasionally so that the jiffy pellets stay damp - moist (not dripping wet). Plant out in the spring.

White Oaks Quercus
Oaks classified into two groups, the White oaks (with rounded leaves) and the Black oaks (with pointed leaf ends; red oaks fall in this group). The White oaks are a little easier to grow from seed than the Black oaks as the White oak acorns are not dormant when they fall from the tree. Gather acorns in late summer as they begin to fall off the trees, some acorns may be infested so discard any with small holes in them. Acorns must never be allowed to dry out as they will die, so if you need to store them before planting, place them in a container with a damp, sterile medium (like peatmoss) and put them in the fridge. You can test the acorns for viability by placing them in a bucket of water overnight before planting; those left floating are likely dead and not worth planting.

White oak acorns can be planted outdoors right after they are gathered, but count on squirrels eating most of them, even with a wire mesh over the seeds. For the greatest number of seedlings, stratify the acorns in your fridge (not freezer). Place them in a ziplock back mixed with damp-moist (not dripping wet) vermiculite, refrigerate and wait for about 3 months. The seeds can be started indoors, place them in a mini greenhouse and cover with a half inch of soil. In late spring, extract the seedlings out of the mini greenhouse and plant in the ground.

Ginkgoes Ginkgo biloba
See Ginkgo Seed Propagation instructions.
Placing your seedlings out doors
All Northern trees need to be grown outside of the home in order to remain healthy. If you have started your tree seeds indoors over the winter, a good time to make this transition for them is mid May, after the worst frosts have passed and before the sun gets too hot. When it's time to bring your seedlings outside, allow them to make the adjustment slowly. Many sources recommend to have seedlings spend just a few hours outside at first and then increase their time outside as the days go on. If you're too busy to do this, just put the seedlings outside in a shady area (during a cloudy day is even better) and every couple days move them to a sunnier area.

Many trees can live in pots outside when they're young; it's a great way to grow and enjoy your trees before you decide where to plant them permanently. It's a good idea to grow the seedling trees in largish pots (1 gallon for example) so that they need watering less often. If you have light coloured pots, they are preferable as they don't collect as much heat as black pots. Also plastic pots in this case are more desirable than clay pots, as unlike clay, plastic will not draw water from the soil through transpiration. During the winter, place your potted seedlings in a sheltered place, you can cover the pots with brush or burlap if you like, but this is not necessary.

Information sources used other than the websites mentioned above

Seeds of Woody Plants in North America
James A. Young and Cheryl G. Young ISBN 0-931146-21-6
Collecting, Processing and Germinating Seeds of Wildland Plants
James A. Young and Cheryl G. Young ISBN 0-88192-057-6
The Reference Manual of Woody Plant Propagation
Michael A. Dirr and Charles W. Heuser, Jr. ISBN 0-942375-00-9

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