Thuja Seeds
The cedars at my cottage are magnificent and produce lots of cones. Can these cones be sown, and if so, how? Is there a general procedure for collecting seeds, samaras, etc. produced by trees and shrubs?
Answer
First, it is not the cones that need to be sown, but the seeds they contain. They must therefore be shelled first. Seeds must also be extracted from trees and shrubs with fleshy fruit (sweet cherries, apples, etc.). However, the husks of dry seeds (maple samaras, nuts, acorns, etc.) should not be removed.
Seeds from “cedar” (Thuja occidentalis), and indeed most trees and shrubs from cold climates, need a period of “stratification” before they can germinate: they must therefore be subjected to cold, damp conditions before being exposed to heat. Either sow them outdoors in the fall for germination the following spring, or sow them in pots indoors and place the pots in the refrigerator. Four weeks in the cold will suffice for thuja, but some other seeds require up to 12 weeks of cold.
As prolonging the period does no harm, it is best to expose any seeds whose specific requirements are unknown to 12 weeks of cold. The soil must remain moist throughout this period, so it is advisable to cover the pots with a plastic bag. Once the cold pre-treatment is complete, simply expose the pots to light and normal indoor heat to achieve germination.
Off-Season Transplanting
We are building a garage and need to temporarily move several rose bushes, a fairly large hydrangea, and three peonies, which we will relocate once the construction is complete. How can we avoid causing them fatal shock by moving them twice?
Answer
Normally, plants are transplanted when they are dormant, i.e. in spring or fall, but it is also possible to do so in midsummer with a little care.
Roses and Hydrangeas
For roses and hydrangeas, it’s relatively easy: prune them back quite severely, to about 45 cm (18 inches) above the ground, then dig them up, keeping a good root ball. Place the plants in the shade while you wait, covering the roots with burlap or newspaper and keeping them moist. These plants may not flower this year, but should do so without any problems next year.
Please note: Not all hydrangeas require severe pruning. For some varieties (Hydrangea arborescens or H. paniculata), this is not a problem. However, for H. macrophylla, excessive pruning can compromise flowering the following season, as this species flowers on the previous year’s stems. That said, in the context of a temporary emergency transfer, the recommendation remains reasonable. You can then choose to prune them less severely, just enough to facilitate transplanting.
Peonies
Peonies pose a different problem. Mature peonies hate being moved and may refuse to bloom again for several years, or even a decade or more, after transplanting… if you transplant them intact. However, I suggest a different tactic. Dig up the peonies (this time without cutting the foliage) and store them with their root balls covered in burlap or newspaper while you wait. When it’s time to replant them, divide them, separating the large, gnarled roots into individual plants, and replant them at the same depth as before. Rejuvenated in this way, your peonies will recover much more easily.
Larry Hodgson has published thousands of articles and 65 books in French and English over the course of his career. His son, Mathieu, has made it his mission to make his father’s writings accessible to the public. This text was originally published in Le Soleil on June 26, 2011.
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