How deep should a raised garden bed be for herbs and vegetables?

For most herbs and leafy greens, 23cm of growing depth is plenty. Tomatoes, capsicums and other fruiting vegetables are happiest with around 35cm, and deep-rooted crops like carrots, parsnips and dwarf fruit trees want 40cm or more. Depth is one of the few decisions you can't change after the bed is full, so it's worth getting right on day one.

How deep do herbs and leafy greens need?

23cm is enough. Basil, parsley, coriander, mint, lettuce, rocket, spinach and Asian greens all carry shallow, fibrous roots. A 23cm tub grows them beautifully and warms up fast in spring — great for quick crops.

How deep for tomatoes, capsicums and other fruiting veg?

Aim for 35cm. Fruiting vegetables — tomatoes, capsicums and chillies, cucumbers, zucchini — feed hard and drink harder. The extra depth holds more moisture and nutrients between waterings, which is the difference between a plant that survives and one that buries you in fruit.

How deep for carrots, root vegetables and dwarf fruit trees?

Go 40cm or deeper. Carrots, parsnips and daikon literally are their roots — a shallow bed gives you short, forked carrots. Dwarf citrus and blueberries also appreciate the extra root run. Our deepest tub is 41cm, and that's the one we point root-veg growers at.

Does a deeper bed have any other advantages?

Yes — slack. A deeper tub holds more mix, and more mix holds more water and nutrients, so everything is more forgiving: you can miss a watering day in January and get away with it. Going deeper than a plant strictly needs is never wasted; going shallower just means watering more often. (Every plant card in our garden calendar shows its minimum tub depth, so you can check your wishlist before you choose.)

Which Corrogarden depth should I pick?

Our tubs come in 23cm, 35cm and 41cm planting depths across the range — and because the tub sits at waist height in the timber frame, "deep enough for carrots" doesn't mean "buried to your elbows planting them". If you're tossing up between depths, the middle 35cm tub is the all-rounder: herbs won't mind the extra room, and tomatoes will use every bit of it.

More garden guides: compost vs potting mix · common raised-bed mistakes · how to fill your bed

What should I plant right now? Our free garden calendar shows what suits your postcode this month — and which pests to watch for. Ready to grow? Browse our raised garden beds or design yours with the garden bed builder.