Use untreated timber. Treated timber can leach chemicals into your soil over time. Macrocarpa is a good choice: it’s naturally rot-resistant and looks great. Before you build, dig a shallow channel where the bed will sit and fill it with gravel. That cuts down soil contact and helps the timber last.

Rotate. Grow a different plant family in each part of the garden every year. Pests and diseases build up when the same crop goes back in the same place, and different families use different nutrients, so rotating stops one patch getting worn out. Some crops, like peas and beans, even improve the soil for whatever follows. Our crop rotation guide has a simple plan for Canterbury gardens.

Check your plants often, looking for holes in leaves or yellowing. Kiwicare Organic Spraying Oil is ready to use and works on common insect pests. You can also pick pests off by hand, and plant a few flowers nearby to bring in bees and the insects that eat the ones you don’t want.

After a couple of months of growing. Your plants take nutrients out of the mix as they grow, so add a layer of compost to put them back. Certified organic compost feeds the mix and keeps the soil life active.