Flower seeds you can start this month (in a greenhouse)

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Start perennial flower seeds, such as delphinium, in your greenhouse in January/February.

In January and February, your local garden centre will have the latest seeds in stock, with each company showcasing their “Best Picks” for the year.

Now is a great time to sow perennial flower seeds in your cool greenhouse. A few of the many varieties that you can try are primula, coreopsis, dianthus, penstemon, delphinium (pictured), gaillardia, digitalis, papaver, viola and rudbeckia. Summer-flowering annuals can be a little trickier, but here are a few of the more durable ones: wax leaf begonia, geranium, cleome, impatiens, forget-me-not and mimulus.

When seeding in January/February, seeds will sprout best at soil temperatures of 20° C (68° F). Heating cables, seedling mats or the space on top of your fridge all work well. Maintain air temperatures of 5 to 10° C (41 to 50° F) and give the seeds 20 to 24 hours of light per day, using a grow light set 10 to 15 cm (4 to 6 in.) above the trays. Spray weekly with a fungicide to prevent rotting.

The tricky point comes when the seeds have germinated and you have all these seedlings. Pinch out their growing tips, transplant them into larger pots and water sparingly (a weekly solution of 10 percent transplanter and water aids in root development).

You’ll want to put them in a very bright spot with cool temperatures so their top growth slows down and their roots continue to grow.

Remember to rotate your pots every few days so the seedlings grow evenly.

Put the perennial plants outside in a protected area in late March, and at the end of April plant them in your flower beds. The annual plants must stay in the greenhouse until mid-May when the soil temperature warms up. Happy seeding!