While many are winding down for the festive season, dedicated gardeners know December is a crucial month for sowing. Getting certain seeds in the ground now can lead to prize-winning vegetables and a continuous supply of fresh herbs next year.
Why December Sowing Gives You a Head Start
As gardening guru Benedict Vanheems points out, the days will soon begin to lengthen. Sowing seeds in December provides plants with a vital early start, allowing them to develop strong root systems before the main sowing season begins in spring. This is particularly true for certain hardy varieties that benefit from a longer growing period.
The Three Essential Seeds for December Planting
1. Onions for Show-Stopping Size
"Now is the perfect time to sow onions from seed," advises Vanheems, especially for those dreaming of giant, exhibition-sized bulbs. The tradition of planting on Boxing Day is upheld for a reason – it gives these alliums the maximum time to swell. For the best chance of growing colossal onions, he recommends varieties like 'Exhibition' or 'Showmaster'.
Start seeds indoors in a well-sifted, all-purpose potting mix. Place them in a warm spot in the house to germinate, moving them to a cooler, bright location like a greenhouse or cold frame once they sprout. Competitive gardeners can use grow lights for the first month to boost early growth significantly.
2. Coriander (Cilantro) for Leafy Abundance
This versatile herb, known as cilantro in the US, is a kitchen staple but can be tricky in summer when it tends to bolt, or flower prematurely. Sowing coriander in autumn or winter avoids this problem, ensuring a lush harvest of the aromatic leaves perfect for curries, soups, and salads.
Vanheems suggests a clever pre-sprouting technique: wrap seeds in muslin, soak them overnight, and then keep them moist. After about a week, the sprouted seeds can be carefully distributed onto a tray of compost. Grow them on a sunny windowsill or in a cold frame, and you could be harvesting leaves in six to eight weeks. Letting a few plants bolt in summer also provides a free supply of seeds for future sowing.
3. Basil for a Winter Windowsill Summer
Bring the scent of summer indoors by sowing basil now. It's an ideal crop for those with limited space, thriving happily on a bright windowsill. Vanheems recommends reliable and affordable 'Genovese' or sweet basil for multiple winter sowings.
Sow seeds thinly in four-inch pots filled with fine compost, covering them with just a whisper of extra medium. Water gently with a spray bottle to avoid disturbing the seeds, then cover the pot with clear plastic to create a humid microclimate for germination. A grow light will accelerate growth during the short, dark days, ensuring you have fresh, fragrant leaves to rub between your fingers long before spring arrives.
Making the Most of Your Winter Garden Space
December gardening offers a perfect antidote to stuffy living rooms and endless television. A greenhouse or cold frame is invaluable, not just for plant protection but as a peaceful retreat. For those without one, a sunny indoor windowsill can become a productive mini-kitchen garden. By taking action this month, you lay the foundations for a more bountiful, flavourful, and rewarding growing season ahead.
