Blooming Times: Early to Rise

It may still feel like winter to us, but plants are responding to the lengthening hours of daylight. Time for some early seed-sowing, says Flo Whitaker

Appearances can be deceptive. Despite their fragile-looking foliage, broad beans and peas, (both culinary and ornamental types) are mostly untroubled by chilly temperatures. Some folk sow them in October/ November and overwinter seedlings in a cold frame or unheated greenhouse. 

This method works because the seedlings produce minimal top growth in winter and put their energies into making substantial roots, which allows for a rapid growth spurt in spring – but, alas, seedlings can be greatly compromised by damage from slugs and mice seekinga tasty midwinter dinner. 

There are lots of mice in my garden, (I’m not complaining; we also have resident owls, and you can’t have one without the other), so I’ve mostly given up with autumn sowings. Instead, I start now; when there’s the added benefit of increasing daylight, which helps prevent etiolated, (‘leggy’) seedlings. 

The large seeds are best sown into individual cells that provide more rooting space – and make transplanting easier. Parsley and perpetual spinach seed may also be cell-sown. All of the above can be planted out in early April – chose a period of good weather to avoid transplant shock.

Some flower seeds germinate well in a cold greenhouse, or on a cool, brightly-lit windowsill. Antirrhinums, (‘Snapdragons’) are naturally slow-growing and can be started now. Cosmos is the most hardworking flower of all. Batches sown from February through to early May will provide colour into October. 

Ammi, orlaya, calendula, nicotiana, pansies and annual salvias, (try S. viridis and S. farinacea), produce superior seedlings in cool conditions, but even the hardiest types appreciate frost protection. Horticultural fleece is feather-light and can be gently draped over greenhouse seedlings without fear of damage. 

Failing that, sheets of newspaper provide a decent level of insulation. If the forecast is severe; move seedlings indoors for the duration and provide a nighttime covering for those on windowsills. 

On the veg patch, use cloches to protect from cold and windy weather. They come in various designs, (and prices!) I prefer to use small-sized ones, as they’re easy to move about and re- position, as required. Place a cloche over the soil for a week before sowing; this allows the surface to dry off and warm slightly. ‘Early’ and globe-type carrots, beetroot, spring onions and cold-tolerant salad leaf mixtures can be direct-sown now to give a harvest in May. 

If you have a heated propagator, a whole new world of seed-sowing is available to you – and plants that have a long growing season will appreciate the additional time gained from an early start. Many greenhouse crops that we treat as annuals in the UK are actually perennials in their native environments. If started late, they reach their optimum fruiting/ flowering peak just as the cooler, shorter days of autumn arrive. If you persistently have trouble ripening tomatoes and suchlike, an earlier sowing date may be the solution. 

Tomatoes, sweet peppers, chillies and aubergines need constant warmth to germinate and develop. If you can maintain a temperature of 18- 200C, they can be sown now; but be prepared to keep them cosily cossetted throughout their lives, otherwise growth/cropping will be severely compromised. These sun- worshippers will tolerate 120C as an absolute lowest limit; they are utterly miserable in cold conditions.

Never use an entire packet of seed in one go. Germination can sometimes be poor or fail altogether, so always keep a back-up reserve. Batch-sowing is particularly useful for vegetables as it provides a succession of crops, not one big glut. Making fortnightly small sowings of lettuce, spring onions, baby carrots and radishes ensures there’s always something fresh and tender to enliven a salad bowl.