This guide forms part of our month-by-month allotment planting calendar.
December is the quietest planting month of the year — and that’s exactly how it should be.
Daylight is at its lowest, soil is often cold or waterlogged, and plant growth has effectively paused. This isn’t a failure or a gap in productivity. It’s a natural pause built into the growing year.
Good December planting decisions are mostly about knowing when not to plant.
Understanding December Conditions on an Allotment
In December, growth is limited far more by light than temperature. Even during mild spells, plants simply don’t have the daylight needed to develop.
Key realities:
-
seeds rarely germinate reliably
-
young plants struggle to establish
-
wet soil can cause rot rather than growth
Anything planted now must tolerate sitting dormant for weeks or months.
What You Can Still Plant in December
Options are extremely limited.
Garlic can still be planted in December if conditions allow. Cloves won’t grow much above ground, but they can begin rooting, which gives them a head start in spring. Only plant if soil is workable — forcing garlic into cold, wet ground usually does more harm than good.
In very mild areas, overwintering onions may still be planted early in the month, but success depends heavily on soil and drainage.
These are the only plantings worth considering for most allotments.
What to Avoid Planting in December
December is not suitable for:
-
direct sowing of vegetables
-
salads or leafy crops
-
root crops for harvest
-
any tender plants
Even if seeds germinate under cover, growth will be weak and difficult to manage.
Waiting is almost always the better decision.
How December Fits Into the Allotment Year
December is about letting the allotment rest.
Beds left empty now aren’t wasted — they’re recovering. Soil benefits from being protected with compost, mulch, or cover rather than forced into late planting.
This pause also creates space to reflect on the year just gone and think ahead to spring without pressure.
A Common December Mistake
The biggest mistake in December is planting simply to feel productive.
There’s nothing to catch up on. The allotment calendar includes quiet months for a reason, and December is one of them.
Final Thoughts
December isn’t about growth — it’s about patience.
If conditions allow, plant garlic. Otherwise, protect your soil, accept the slowdown, and let the year close naturally. A calm December leads to a far better start when the growing season begins again.