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I Need Colour!

Our growing season is so short that we all want to jump in and get colour into our gardens as soon as we can. April has been chillier than normal this year, so greening up is taking its time.  The urban landscape is still mostly shades of brown but there are tiny pops of green and bits of colour showing up here and there. I am glad to see the green tips of the daffodils and scilla bulbs peeking through the mulch around my lilacs, and on inspection of my very sheltered front flowerbed, I find last year’s violas have overwintered and are looking fresh, green, and ready to grow. Pansies and violas are the perfect early annual as they can handle both the chill of early spring and the unexpected snow that May often throws at us. 

I Need Colour!

I Need Colour!

As with all greenhouse-grown plants, they must be hardened off before you put them outside for the season. Hardening off is the process of acclimatizing plants to the full sun and wind conditions they don’t encounter in the greenhouse. Plant foliage burns in the sun just as pale winter skin does after a long sheltered winter indoors, and stems need gradual exposure to gentle breezes in order to develop the strength to withstand strong summer winds.

I put my plants out for two or three hours in the morning sun or shade for a day or so, and then gradually increase the time spent outdoors. By the end of a week (depending on the weather forecast, of course) they are ready to be outside full-time. If you do put your plants out in early to mid-May (temperatures need to stay above zero) be prepared to bring them indoors should a cold snap arrive. The garage is fine for a day or two, but if you must keep your plants in there for an extended period, ensure that there is excellent ventilation and adequate light. Garage syndrome is real (read this blog post).

I am amazed to see that the yellow-red Pocketbook Plant, or Calceolaria calynopsis, I planted last year has unexpectedly survived the winter under a deep cover of snow - albeit with difficulty. I planted it in early July last year, and it put on a stunning display right through to the end of July in a bed that receives morning sun. It can clearly handle cool weather, so perhaps this might be a good one to try for early colour. 

Anemone coronaria is another cool-weather annual plant that puts on a bright show of flowers in spring. Its fern-like foliage can handle lower temperatures, but it will need covering or bringing in if temperatures go to zero overnight.

Dianthus too performs best in cool weather, and there is a new colour this year that will add a gorgeous pop to the landscape. It’s called Coronet White Purple Eye and has a larger bloom size than most dianthus. I’m thinking it will look lovely in a perennial bed, tucked in beside Bergenia cordifolia, or in a pot with some blue and white Spring Matrix pansies.

If you prefer daisy-type flowers for a spring show, you can’t go wrong with the sun-loving African Daisies, Akila osteospermum, or the Cineraria Senettis which prefer part-shade.

And last, but not at all least, there are the Regal Elegance Geraniums, aka Martha Washingtons. The pink and burgundy Lilac Majesties make my head turn every time I walk past them in the greenhouse. They prefer part sun so would make good planter companions for pansies.

No matter whether you are selecting plants for an early spring patio container, or for planting when it warms up, make sure you take the time to harden them off before putting them outside. I have it on good authority that fuchsias and coleus are the plants that suffer most when put outside too early. Other tender annuals such as begonias, sweet potato vines, and tomato plants also need to stay in a toasty warm place until all danger of frost has passed.