8 ways to prepare your vegetable garden for winter in New Zealand

There are many jobs you can do now to prepare your vegetable garden for winter

Now it is autumn, its a good time to tidy up and prepare your vegetable garden for winter. This makes it easier to grow more veggies either over winter, or the following spring.

Your veggie garden may look a bit like mine, as it is almost at the end of the summer harvest. The plants are a bit straggly, and some overripe vegetables such as tomatoes are falling to the ground. I was lucky to have a good summer with an abundance of capsicums, tomatoes, eggplants, and cucumbers. But now it’s time to look forward to the next season. These suggestions will help you prepare your vegetable garden for winter.

1. Clean up the vegetable garden beds

Some diseases, pests and funguses can stay on old vegetable plants over winter, so it’s best to clear them out. Cut back and remove dead plant material like leaves and stems, and fallen fruit or vegetables. Add them to your compost bins.

Some gardeners do leave some plants to provide protection to the soil over winter, but I prefer to remove them all. However, I am trialing a ‘cut and leave in place’ method in a couple of my vege beds this winter. I am going to pull up or cut down perennial vegetable plants like capsicums and eggplants, and leave them on the surface off the soil, to wither in the sun. Then I will cover with compost and mulch – see below for more details.

I sometimes let my chickens into the vegetable gardens at this stage. They do a double duty; they peck up any fallen vegetables and bugs, and the poop all over the ground adding some great fertilizer!

2. Remove any problem weeds from the vegetable garden

Now is the time to tackle any invasive weeds in your vegetable garden. This could include ground cover weeds, vines, and grasses. See the Weedbusters website for some very useful information.

Dig up or pull out weeds, to stop them taking over.

Where to put weeds?

• If you have a compost bin that gets very hot, you could put them in there – it needs to get hot enough to kill invasive weeds, including the seeds. This is very important if you plan to use the compost on your garden in future; if the weeds are still viable, they will spread wherever you put the compost in future.
• I use a separate compost bin that is exclusively for problem weeds. I leave them in there to decompose, and I don’t use this compost in my garden.
• Dispose of weeds carefully – if it is a small amount, they can go in your household rubbish bin. If it is a larger amount, take them to an approved landfill, and cover them with a tarpaulin if you are using a trailer to transport them.

Weedbusters have excellent information on disposing of weed waste properly.

3. Add nutrients to your soil (amendments)

Autumn is a good time to replenish the nutrients in your soil that spring and summer crops may have used up. You can add manure, compost, or commercial fertilizers.

It may be useful to get a soil test done before you add ‘amendments’.

What Are Soil Amendments?

A soil amendment is anything added to soil to improve its abilities, including water retention and absorption. The goal of soil amendments is to provide a healthier environment for roots to grow.

From https://www.thespruce.com/soil-amendments-1402460

Soil tests results will tell you:

• Soil pH
• Levels of potassium (K), phosphorus (P), calcium (Ca), magnesium (Mg), and sulfur (S)
• Level of organic matter

You can then add the amendments that your soil needs to be as healthy as possible.

4. Plant crops in your vegetable garden – either cover or vegetable crops

4a . Plant cover crops

It’s a good idea to rotate where you plant different crops in your vegetable garden each year. And if you can, plant a green crop or manure crop over winter, to give the soil a boost.

Different plants take different nutrients from the soil. If you plant them in the same spot every year, the soil will become deficient in those nutrients. This can lead to increased risk of pests, diseases and poor crops.

I grow a green crop / manure crop every couple of years in my vegetable beds. You can buy these in single types of crops such as oats, lupin, or peas, or you can buy bags of mixed green crop seeds. I have bought them from DIY stores with garden centres, or online from companies like Kings Seeds: Cover Crops from Kings Seeds

4b Plant winter vegetable crops

There are many vegetable plants that grow over winter in temperate parts of New Zealand. These include:

• Beetroot
• bok choi
• broccoli
• cabbage
• carrot,
• cauliflower
• celery
• coriander
• kale
• leek
• lettuce
• mesclun
• onion
• radish
• rocket
• silverbeet
• spinach
• spring onions.

To learn more, please read my article Best vegetables to grow in winter in NZ

5. Top up mulch

Mulching the vegetable garden in winter is just as important as it is in summer. It helps reduce water loss, and keeps weeds down.

In winter though, it also helps to keep the soil temperature more even, compared to bare soil with no layer of mulch to regulate temperature. It can protect plants roots from frosts, and adds more nutrients as it breaks down.

I use tree mulch that has been sitting in a pile since last winter. We usually get a couple of trees cut down for firewood each year. The arborists mulch the branches, leaves and bark, and leave it in a huge heap. By the time we put it on the vegetable garden, it has started to break down, and is rich and smells deliciously earthy.

6. Harvest compost from your compost bins

Compost from your bins will likely be in a great condition, after the warmth of summer. Now is a good time to add this to your vegetable garden.

And refill the empty compost bins with autumn leaves, grass cuttings, and kitchen waste.

For more information on composting, read my guide How to make compost step by step

7. Review how your summer vegetable growing season went

In autumn, it’s a perfect time to think about what grew well and what was not such a success. This is handy for when you plan your vegetable garden for next spring.

I noticed that this year, I had a successful crop of cucumbers. However, I need a better framework to grow them up, as my current set up was too small to support all the vines and vegetables. So I will add this to a list of jobs to do over winter.

Did you find that some vegetables performed better than expected? Can you pinpoint why they were so successful?

And of course, what about the opposite? What a flop crop this summer? And what can you do to improve if you try it again next year?

Some factors are hard to control, like the weather. But some things are choices you can make, such as where you plant your seedlings, and the varieties you plant.

8. Clean your gardening tools

It’s important to clean your gardening tools after every use. However, autumn is a good time to give them a thorough clean and sharpen, to keep them at their best.

Tips for looking after gardening tools:

• Clean tools – rinse with water to get rid of any dirt, and dry them with a cloth.
• Oil tools to prevent rust – vegetable based oils are fine, rub a layer over the metal parts.
• Remove any rust – sand away rust with sandpaper or a wire brush, and add a layer of oil.
• Sharpen the blades – take them to a professional tool sharpener, or do this yourself if you know how (carefully though).
• Store tools – hanging tools up or storing them in a cupboard in a shed will keep them safe.

What are you planning to do with your vegetable garden for winter?

Did this help you with any new ideas? I’d love to hear from you in the comments.