What to sow and grow in December
In December frost protection is the main focus for gardeners. All tender plants should now be indoors, in a greenhouse or be protected by frost fleece or cloches, but now is also the ideal time to plant garlic and you can still sow some seeds if you have a greenhouse, a cold frame or on a windowsill facing south.
Here are our favourites for sowing and planting in December...
Plant Garlic - indoors or outdoors
It’s traditional to plant garlic on the shortest day of the year (around 22nd December) so that you can harvest from July.
In the milder areas of the country you can plant garlic in the ground outdoors if you warm the soil first by covering with fleece or a cloche. Everywhere else you can start the plants in seed trays and small pots and keep them indoors or in the greenhouse until it’s warm enough to replant the young plants outdoors from March.
Don’t worry too much about frosts, garlic (just like winter peas) produces better yields if subjected to a period of winter chill.
1. Break garlic bulbs into individual cloves taking care not to damage the cloves.
2. If you live in a mild area plant the cloves in soil that has been under fleece or a cloche for a few days. Plant the cloves 10cm apart pushing the cloves into the soil so their tips are just below the surface. Cover with cloches or fleece tunnels in frosty weather.
3. In cold areas or for earlier harvests plant the garlic cloves in seed trays. Water well and place the seed trays in a cool greenhouse, cool spare room or outdoor cold frame. They will be ready to plant outdoors in March or April.
Keep garlic well watered during dry weather so that the cloves swell.
Sow Broad Beans
You can sow Broad Beans until the middle of December. Protect the young plants with fleece in cold snaps because frost and snow can damage young autumn sown plants causing the plant tissues to become soft and transparent resulting in the plants toppling over and not recovering, covering with frost fleece will prevent this. Choose hardy broad bean varieties such as Aquadulce Claudia and Super Aquadulce. Protect the seedlings from the wind by growing in a sheltered spot.
In the greenhouse / on a windowsill
If you have a greenhouse or a sunny indoor windowsill sow fast growing herbs (basil, parsley, dill and chives) and sow hardy salad leaves such as Rocket, Mizuna, Land Cress, Valdor, Arctic King and Winter Gem. A small unheated planter/propagator with a lid is very useful for getting seeds off to a good start at this time of year.
Once the seedlings are visible protect them from frost with fleece or a cloche, or if you have a Vitopod propagator use that set to 5C.
If you're new to sowing seeds watch our video
Plant fruit outdoors
December is a great time for planting strawberries under frost fleece for early spring fruit and you can also plant blackberries, gooseberries and blueberries any time between now and the spring.
Sow Decoratives - in the greenhouse / indoors
Sow Begonias, Geraniums, Antirrhinhums (Snapdragons) and Laurentia in a greenhouse or a cool spare room for a head start to the season and Cyclamen prefer cooler temperatures so sow them between now and March.
Plant Bulbs - outdoors
If you hurry you can plant spring bulbs before the first frost. Daffodils, crocus and tulips are our favourites. Only buy bulbs that are plump and firm.
Plant bulbs with the top facing upwards (if unsure plant the bulb on its side). Plant them two to three times their own depth spaced two bulb width apart. When adding the soil back make sure there are no air spaces around the bulbs.
Keep the compost moist and protect from frost with double thickness frost fleece or by wrapping with bubble wrap. Cover with chicken wire until the shoots appear, this will prevent squirrels and other garden wildlife from digging them out.