As the temperatures cool and the sun begins to dip lower in the sky, your vegetable garden may start to look a bit bedraggled. This is a completely normal part of the cycle of an annual vegetable garden, but it doesn’t mean your work is done for the year. Preparing your vegetable garden for winter is an important final garden task that will set you up for success the following spring by reducing pests, diseases, and weeds while improving your soil.
The three most important steps to prepare your garden for winter are to remove any hardy weeds, compost or burn all of your vegetable residue, and cover any bare soil with a cover crop or mulch.
Removing hardy weeds in the fall is important because they’ll continue to grow and expand their root system through the winter. When it comes time to prepare your garden for spring, it’ll be much harder to remove these well established weeds.
In some cases, hardy weeds can propagate themselves through their roots. And if you allow them to get established over the winter, they can be almost impossible to eradicate. In our gardens we like to run a tool called a scuffle hoe through the soil to uproot any weeds before raking them out of the garden so they don’t reestablish themselves. There will still be weed seeds left behind that will germinate in your garden the following season, but they will be much more manageable than the monster weeds that would have survived the winter.
Composting your vegetable residue prevents the transmission of insect pests and diseases to the next season. Because specialist insect pests like squash bugs and bean beetles can only survive by feeding on specific garden crops, they go dormant when these crops are no longer available.
Luckily for us, they typically spend that dormancy period hiding in the garden residue of their crop of choice. If we remove this from our garden and either hot compost or burn it, we can disrupt their lifecycle and reduce their population for the following season. The same is true of many fungal and viral plant diseases which spend the winter in dormancy waiting for a suitable host in the spring.
It’s important to note that a cold compost pile will not destroy plant diseases or insect pests so if you don’t have a hot compost system, I would recommend adding the garden residue to your next bonfire instead.
If you’ve removed the fall weeds and composted all of your garden residue you’ve done yourself a huge favor for next spring, but you’ve also created a new problem—bare soil. Bare soil in your garden should be treated like an open wound on your skin. It leads to erosion, nutrient depletion, and the loss of important soil organisms.
The best way to cover your bare soil through the winter is by using a cover crop. We like to use a combination of annual ryegrass and crimson clover. The ryegrass develops deep roots that retain nutrients and provide habitat to beneficial soil organisms while the clover produces nitrogen through a symbiotic relationship with bacteria in its roots.
Most cover crops need to be planted about a month before the average first frost in your growing zone in order to establish themselves for winter. If you don’t have enough time for a cover crop to get established before the frost, another good option is to cover your bare soil in a thick layer of compost or mulch for the winter.
While these three tasks can sound like a lot of work for little reward, the payoff is well worth it in the following spring. You’ll save time on weeding, have fewer pests and diseases to contend with, and due to your thriving soil, your plants will flourish.