Niwa4×8 raised bed garden layout plans
A 4×8 bed is thirty-two squares. Here is exactly what to put in each of them, in three plans for three different goals.
Four feet by eight feet has become the default raised bed size because it works: you can reach the centre from either side, it cuts from standard lumber, and thirty-two squares is enough to matter without becoming a chore.
The hard part is not building it. It is deciding what goes in the thirty-two squares.
Depth, orientation and soil
Depth. Six inches is the minimum and only suits salad, radish and herbs. Twelve inches handles almost everything. Eighteen inches is worth the extra soil cost if you want carrots, parsnips or potatoes, or if you are building over concrete or compacted clay.
Orientation. Run the long axis east to west, and put tall crops along the north long edge. That gives you an eight-foot trellis line that shades nothing.
Soil volume. A 4×8 bed twelve inches deep needs 32 cubic feet, just under one cubic yard. Roughly a third compost, a third topsoil, a third aeration material. It will settle two to three inches in the first season. Top up with compost, do not compact it back down.
Paths. Eighteen inches minimum between beds, two feet if you use a wheelbarrow.
Plan A: the first-year bed
Forgiving crops, a real harvest, nothing that needs specialist attention.
| Row | Squares 1-8 |
|---|---|
| Row 1 (north) | Tomato ×1, basil ×4, tomato ×1, basil ×4, tomato ×1, basil ×4, tomato ×1, marigold ×4 |
| Row 2 | Pepper ×1, pepper ×1, bush beans ×9, bush beans ×9, cucumber (2 sq), chard ×4, chard ×4 |
| Row 3 | Carrot ×16, carrot ×16, beetroot ×9, beetroot ×9, spring onion ×16, radish ×16, carrot ×16, radish ×16 |
| Row 4 (south) | Lettuce ×4 ×4 squares, spinach ×9, spinach ×9, parsley ×4, marigold ×4 |
Why it works: nothing in it fails easily. The radish squares are ready in a month and become your first succession sowing, which teaches the most important habit in vegetable growing. Total: about 180 plants.
Plan B: the high-value bed
Maximum shop-price value per square foot. Everything here is expensive to buy and prolific to grow.
| Row | Planting |
|---|---|
| Row 1 (north, trellised) | Cherry tomato ×1 ×3 squares, mangetout ×8 per square ×5 squares |
| Row 2 | Basil ×4 ×3, coriander ×4, dill ×4, chilli ×1 ×3 |
| Row 3 | Salad leaves ×4 ×4 squares, rocket ×9 ×2, pak choi ×4 ×2 |
| Row 4 (south) | Spring onion ×16 ×2, chives ×16, parsley ×4, thyme ×4, mint in a sunken pot, strawberry ×4 ×2 |
Why it works: a supermarket basil pot costs the same as a seed packet that fills three squares for a season. Cut-and-come-again salad from four squares replaces a bagged salad every week for months. This bed pays for its own construction in one year. Note the mint is in a sunken pot, never loose in a bed.
Plan C: three harvests from one bed
The same thirty-two squares, worked in three passes. This is where a raised bed doubles its output.
Spring (6 weeks before last frost)
Peas on the north trellis, spinach, lettuce, radish, early carrots, broccoli, pak choi. All cool-season, all tolerant of frost.
Summer (1-2 weeks after last frost)
As spring crops come out: tomatoes and beans replace the peas on the trellis; peppers and courgette take the brassica squares; basil takes the spinach; main carrots and beetroot fill the rest.
Autumn (10-12 weeks before first frost)
As summer crops finish: spinach, rocket, lettuce, radish, pak choi and turnip go back in. Garlic goes into four squares in late autumn for next summer.
Why it works: most beds sit at one crop per square per year. This runs two or three. It requires knowing your frost dates precisely, which is covered in when to plant vegetables in your zone.
Rules all three follow
- Tall on the north edge. Non-negotiable in the northern hemisphere.
- Trellis anything that vines. Peas, beans, cucumbers, small squash and indeterminate tomatoes all go up, which roughly triples what a bed holds.
- Never fill every square in April. Keep four to six for succession sowing or you get one harvest wave and then bare soil.
- Aromatics between fruiting crops. Basil, chives, parsley and marigold in the gaps. See what to plant with tomatoes.
- Write down what went where. Next year's rotation depends entirely on this year's record, and nobody remembers it in March.
Building your own
These plans are starting points. Your sun, your climate and what your household eats will change them, and the moment you change one square, the spacing, dates and rotation all need rechecking.