Forcing branches of early-blooming trees and shrubs is an annual tradition many gardeners practice, in fact, it is often one of the first gardening skills we learn as a child ( I admit, it was my entry drug!), but forcing in January can be more challenging in Zone 5, since spring is still three or four months away. The closer one gets to warm weather, (i.e. the longer the days become), the faster branches will force. In fact, many branches will not force if the plant has not received a required period of cold, and short-day photoperiod, which is why some trees and shrubs such as lilac and magnolia are more challenging to force, that is, unless you are about 3 weeks away from their natural blooming time.
As we are planning this far-too-large birthday party, (Dad's 100th birthday), I wanted to force lots of branches to decorate the house with, and to save money. I often construct a giant arrangement in the studio for events here, so I have the timing pretty much planned out. I know I can force the witch hazels and yellow flowered Cornus mas in enough time, as they are almost ready to bloom now, but other branches need a little more care and even pre-treatment. I remember many forcing tricks, from my horticulture classes from my college days when we would force trees for the New England Spring Flower Show in Boston, and for another one which was held a month earlier, sponsored by the Worcester County Horticultural Society in my home town of Worcester.
Those years taught me that with early planning, many trees can indeed be forced, tall ones like American Elm and Maples, even forced into full leaf, and shrubs like rhododendron and lilac, but I am not about to bother with wrapping trees with plastic, applying mist and damp cotton which we would wrap around magnolia and lilac buds), this time I am just forcing easy trees. Easy forcing woody plants you probably already know of, Forsythia comes to mind, and yes, I picked a few from a shrub that Joe told me was growing behind the chicken coop ( I really don't like forsythia, but I do like some for forcing, which reminds me that I really want to plant a forcing garden out back, but that's another post).
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Branches from the garden are plunged into a bucket of warm water in the greenhouse to be forced for a party we are having in two weeks. |
If you want some January and early February color, try forcing some witch hazel ( Hamamellis), early dogwoods like Cornus mas, or Cornelian Cherry, with small yellow fragrant flowers that are not dogwoody at all, and some early blooming Star Magnolia, Magnolia stellata. These woody plants require a little more care when attempting to force this early, I like to cut them two weeks in advance of the date needed, plunging them into buckets of warm water in the sunny greenhouse, so that they can experience a week and a half of temperature shifts above 32º F, which is important, especially for more challenging plants like the magnolia.
Lastly, I picked some Willow (Salix) species, I must admit that I don't know exactly what species it is, but I do remember that I purchased a potted, named selection of a pussy willow and it was obviously selected for its large catkins. I think I purchased it at Weston Nurseries in Hopkington, MA a few years ago. If one demands impressive pussy willows, one must tolerate the messy, aggressive if not ugly shrub for I don't care what anyone says, 99.9% of willows are not landscape worthy. We cut ours down almost completely to the ground (coppacing it) every two years, leaving about 10 inches of 1 inch diameter trunks, properly called 'stools'. In no time, the stools will produce water shoots which can reach tremendous heights in just one season. These whips will produce the largest buds, which is exactly what one wants, and this is exactly the way commercial growers of willows produce their canes. Our shrubs rewards us with 10 foot long canes and whips which we can force in mid winter. Just be sure to plant your choice Pussy Willow in a location where no one will ever need to see it.