How to Prepare Your Soil for a Winter Vegetable Garden

Soil is where a winter patch is either won or lost, and I say that as somebody who spent the first few years quietly giving up on the garden around May and not picking it back up until spring. The weather here is mild enough that you can grow right through, so if the beds are in decent shape before it gets cold you get a run of vegetables through the months when everybody else's garden is sitting there doing nothing.

This is what I do to get mine ready.

Clear the beds out first

At the end of the growing season I pull out the dead plants and the weeds, because pests and diseases will happily sit in that material over winter and go straight back into whatever I plant next. It is a boring job and it is the one that saves you the most grief later on.

Find out what your soil is actually doing

Most winter vegetables are happy somewhere between a pH of 6.0 and 7.0, which is slightly acidic through to neutral. A cheap test kit tells you where you sit, and from there you can lift the pH with garden lime or bring it down with sulphur. Testing is one of those things people skip, and then they wonder why the cabbages and the broccoli sulk.

Get organic matter into it

Compost or well rotted manure does two jobs at once, because it feeds the soil and it fixes the structure at the same time. I spread about five to eight centimetres over the bed and work it in properly. I also use GOGO Juice and Popul8 from Neutrog to look after the microorganisms, and with regular application both of those have made a real difference to what my raised beds produce compared to when I first built them.

Mulch, and be generous about it

Mulch insulates the soil so it holds warmth and moisture, and it stops the winter rain washing the surface away while keeping the weeds down. I use straw, lucerne hay, the leaves off my fruit trees and grass clippings. The part I did not expect is the worms. There are far more of them in my beds now than there ever used to be, and that is the mulch doing it.

Think about a green manure crop

Clover or rye sown over an empty bed puts organic matter back in and opens the soil up so air can get through it, and then you dig the lot in before you plant. It is a slow way to improve a bed and it works.

Sort the drainage out before the rain does it for you

Winter rain will waterlog a bed and rot the roots off everything in it. I do not have that problem now because I garden in raised beds, but I certainly had it when I started, because the soil I started with was clay and it held water like a bathtub. If you are on clay, gypsum worked through the top layer is the usual fix, and raising the bed even a little bit helps more than people expect.

What I actually grow over winter

After years of experimenting I have landed on a fairly short list, and it is short because I keep picking the same sort of thing: something that crops continually, or something that grows fast. Spinach, coriander, peas, broad beans, garlic, rocket, cos and frilly lettuce, broccoli and cabbage. I grow potatoes all year round and I could not tell you why they are so happy in the raised beds, but they are, especially under the crop covers.

I have grown cauliflower successfully and I do not bother much any more, because it sits in a bed for a long time and gives you one head at the end of it. Cabbage and garlic are the two exceptions I make to my own rule, and both of them are worth it.

Crop covers are the bit that changed everything

I started putting clear reinforced tarpaulins over my raised beds after a customer up in the hills told me he did it, and honestly that one change did more for my winter harvest than anything else on this list. Before that I would get a token crop of beans and spinach and then more or less abandon the garden. Now the summer crops run longer at both ends and I grow right through, so I buy very few vegetables from the supermarket.

Shop related products

• Brunnings Garden Compost with Seaweed 25L. Organic matter and seaweed in the one bag, dug through the bed before planting.
• Whoflungdung Mulch 20kg. Mulch that breaks down into the bed rather than just sitting on top of it.
• Neutrog GOGO Juice 2L. The microbe and seaweed tonic I keep using through the cold months.
• Neutrog Popul8 1L. Feeds the soil biology rather than feeding the plant directly.
• Brunnings Garden Lime 3kg. For lifting the pH when a test says the bed has gone sour.

Did you know we also stock lucerne bales in the shop, along with garden gypsum and dolomite for anyone working with clay. They are not listed on the website, so give us a ring on (08) 8536 4333 to check what is on the shelf.

The rest of the soil gear is in the garden centre, and if you are not sure what your bed actually needs, bring a photo of it in and we will work it out together.

More from the garden

• A Beginner's Guide to Building Good Soil for Your Vegetable Garden
• How to Make Compost at Home Without It Going Wrong
• Five Flowers to Grow for Colour in Winter

Cheers, Candeece. Still the one who forgets which bed the garlic went into, every single year.