Few people sow seeds of polyanthus and winter-flowering pansies – it’s far easier to buy young plants from the likes of B&Q or nurseries and garden centres.
Which makes sense, both economically and in terms of logistics because a lot can go wrong with seeds. While pansies usually germinate quite well, polyanthus can test the resolve of many a gardener.
Although both species are grown in virtually identical conditions, there is one big difference. Sowing seed for next spring’s polyanthus and winter-flowering pansies is normally done in June. Both need a reasonable, moist compost and a small amount of heat to help them to germinate – 60F should do fine. But whereas the seeds of the pansies need darkness to encourage them into life, those of the polyanthus do not.
So, cover the seeds of the pansies with compost but simply sprinkle the very fine seeds of the polyanthus on the surface of the compost because they need light to help them germinate. They also take quite a while to grow until they flower.
Once the seeds have been sown in their trays or pots, cover the containers with cling film. When the seedlings appear, wait until they are large enough to handle before potting them up until it’s time to plant them outdoors, in autumn.
So, this June, by all means keep pansy seeds in the dark, but with the polyanthus seed – let there be light.
Alternatively, buy perfectly-formed polyanthus plants when they appear in the garden centre or, even better, spend an hour or so right now lifting and dividing established plants.
Polyanthus are hardy beasts quite capable of growing into large clumps. There comes a time when they are too big for their own roots.
When there are few flowers left and the foliage is just a mass of browned-off and anaemic leaves, prise up the plants, clean off the old soil or compost from the roots, and then split them. A two-year old plant should provide many perfect clones to pop into individual pots.
Why bother sowing seeds?