How to keep your Christmas plants alive into the new year

Poinsettias have done their service, brightening up corners of our homes over the holidays. Now, should they stay or should they go?

Many people may also have been given or purchased amaryllis bulbs or a Christmas cactus plant over the holidays, and need advice on growing them.

She had one that was her grandmother's Christmas cactus and it was over 75 years old.— Peter Meijer, Van Kampen's greenhouse

P.E.I. greenhouses, garden centres and florists offered their suggestions.

Poinsettias

Van Kampen's Greenhouse in Charlottetown raises 4,000 poinsettias every year, starting in mid-July with four different varieties of 2.5-cm tall rooted cuttings. 

"Most people do just replace them. To be completely honest, that is OK by me," said Peter Meijer at Van Kampen's.

But they can be maintained from year to year, he adds, and some people do.

"It's not that difficult to do" with proper watering, temperature and lighting, he said. "The number one thing is to not over-water it," Meijer said. 

People see the leaves falling from the bottom stems of their poinsettias and think they need water — but the problem is usually the opposite, he said. 

Water a consistent volume each time — Meijer suggests 175 ml or 3/4 cup — and let the plant dry out thoroughly between waterings, which will depend how dry your house is. 

"You'll find the schedule your plant wants to be on, whether that's five days or seven days or what have you," he said. 

The other main thing is to keep poinsettias away from cold drafts. Even a ride home from the store in a cold vehicle can sometimes spell the end for a sensitive poinsettia. 

"It won't tolerate any time below –5," Meijer said, and the leaves will shrivel. Keep them anywhere from 10 to 30 C, with the ideal around 18 degrees.

Keep them in filtered sunlight through the winter, he advises, then after the risk of frost passes in June they can be put outdoors in the ground until fall. Meijer sticks the pot right in the ground and rarely waters it.  

Even outdoors, indirect sun is best. Meijer plants his behind a hydrangea.  

Finally, poinsettias need shorter days to be forced to change colour again from green to red in the fall. When daylight gets shorter outside, poinsettias need to be reminded — and the light from household bulbs can fool them, so they have to be put away in a dark closet or room at night. 

Amaryllis

Veseys Seeds in York sells thousands of amaryllis bulbs every year, said in-house horticulturist Heidi Wood, and they're fun to grow.

Resembling a giant onion, amaryllis bulbs sprout a slim green shoot 45 centimetres tall topped by a succession of several showy, lily-like blooms. They come in many colours but red and white are popular at Christmas.

Although they often come in a boxed kit that includes soil and a plastic pot, ditch the plastic for a terracotta pot, Wood advises. They're heavier, which will prevent the top-heavy blooms from toppling the plant, and they're porous, so they drain well.

Wood advises first soaking the amaryllis in water up to about the halfway mark for about 24 hours.

Then plant the bulb — alone or in a grouping of several — in quality potting mix with peat moss, vermiculite and perlite, with the top quarter or "shoulders" exposed, Wood said. Allow enough room at the sides and bottom of the pot for water to circulate around the bulb. The soil should be moist but not "mucky." 

Once the bright green stalk sprouts from the bulb, water it carefully, she said. "Treat it like a house plant... stick your finger in half an inch [1.25 cm]" to see if the soil is moist, and err on the side of drier over wetter to prevent rot.

Once the stalk reaches at least 45 centimetres (18 inches) it may need some extra energy, so Wood suggests a water-soluble fertilizer every 10 days or so until it finishes blooming, in about three weeks. 

Keep the amaryllis out of direct sunlight and heat. Let the flowers and stalk shrivel, then cut it down to about one centimetre. 

"Then it's time to put the little guy to rest for a little while," she said. The plant will have waxy, succulent green leaves, she said, and are not unattractive — so just keep it as you would any houseplant.

To prepare for blooming again next season, put the amaryllis in a cool, dark place like a basement from August to mid-October, keeping it watered minimally. 

Mid-October, reintroduce the amaryllis to daylight and repeat the above steps to get a bloom by Christmas.

Christmas cactus

"They thrive on neglect," said Vikki Sweeney, co-owner of Flower Buds florist in Charlottetown. Christmas cacti, along with "anything bloomy," such as orchids and cyclamen, are now popular at Christmas as gifts that can last for decades. 

Like any cactus, Sweeney said, don't over-water your Christmas cactus. When you do, fertilize with a liquid fertilizer at half strength, and make sure your pot has excellent drainage so the roots are not sitting in water, she advises. 

"They like to stay fairly tight in the pot," Sweeney said, putting their energy into making greenery and flowering rather than growing roots. 

Like a poinsettia, they are forced into blooming when days shorten, and some will also bloom again at Easter, when days become longer.

When the plant does bloom, keep it stationary, Peter Meijer at Van Kampen's emphasizes. 

"Even a 10-degree rotation of a pot when it's in full bloom will cause the blooms to twist off and actually fall off," said Meijer. The plants become used to the sunlight pattern in the room and if it changes, the plant will "reach for sun," causing the blooms to twist off. 

"We had a lady two years ago, came into the greenhouse. She had one that was her grandmother's Christmas cactus and it was over 75 years old," said Meijer.

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