2010-11-18 / News

Growing flowers in the heart of winter

The Island Garden
By Roger Marshall

Growing flowers over the winter poses more problems than most gardeners will admit. Flowers need to be tricked into blooming so that you can enjoy their blossoms in the dead months rather than in spring.

Most of us are familiar with growing flowers such as paperwhites in the middle of winter. Simply put new bulbs in water and let them go. In about six weeks you will have sweet smelling winter blooms.

There are several ways to get more winter flowers. The easiest is probably to stick spring blooming flower bulbs in the refrigerator or even the freezer for a few months and then plant them and put them in a warm room. They will spring (like the pun?) into bloom even in the middle of winter. You can also try this trick with primula, anenomes, wind flowers, and Siberian squill. Daffodils, jonquils, and other spring flowers are particularly nice when done this way.

Simply pot a few up now before the ground freezes, put them in a plastic bag to prevent them from drying out and put the entire package in your freezer. Clearly mark the package so that nobody will use it for soup. Leave it for at least six weeks before moving to a sunny warm windowsill.

Another way to get a lot of flowers is to keep the flowers that you already have going. For example, mandevilla vines have a ton of flowers. By potting up the plant or bringing the existing pot indoors, the mandevilla plant will keep going all winter long. Some of my mandevillas are now seven years old. They get cut back each winter and moved into the greenhouse, but in spring the vines grow so vigorously that they have to be twined onto trellis by mid-May.

With that said, I far prefer the flowering plants with a good aroma. When the key lime, orange and lemon trees come into bloom in the greenhouse, the aroma is wonderful. It often seems that every hibernating bee and wasp for miles around knows it and they seem to fight to get into the greenhouse. When I bring these small trees into the office, it’s not unusual to have bees flying around the office in the middle of a warm day in February.

Orchids are another plant that have both shape and aroma and can be forced into bloom during winter. To me orchids are like cats, they do exactly what they want. They bloom whenever they want. I have yet to figure out how to get an orchid to bloom when I want it to bloom. But I have found an answer. Simply grow enough orchids that one or more are always in bloom. Take the one in bloom indoors and everyone thinks you are a genius for getting it to bloom in winter – little do they know!

Once you have some experience with getting plants to bloom in winter you know how long in advance you need to be freezing and forcing the plant. For example, if you want red leaves on your poinsettia for Christmas you should have been covering and cooling it already. If you want paperwhites to decorate the Christmas table you still have time. Plant them in early to mid-November. They take about six to seven weeks to come into bloom.

Remember to keep the forced plants. If you put them outdoors in spring, they will revert to their normal growth period next year. Of course, if you don’t want to grow flowers, you can force rhubarb and other fruits, but that’s a story for another week.

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