Asparagus crowns go 40 cm apart, in a bed for twenty years

Plant asparagus crowns about 40 cm apart, in rows 45 cm apart. The usual range is 30 to 45 cm between crowns. Each one goes in a trench about 20 cm deep with its roots spread over a low ridge of soil, so the buds end up about 10 cm below the surface.

Because an asparagus bed crops for twenty years or more, it’s worth getting the spacing right at the start. The plant spacing calculator shows how many crowns fit in your bed.

Spacing at a glance

	Spacing
Between crowns	About 40 cm (30 to 45 cm)
Between rows	45 cm
Square foot garden	1 crown per 30 cm square
Trench depth	About 20 cm
Buds below the surface	About 10 cm

Why asparagus needs the room

A one-year-old crown looks like a small spider of roots. Over the years it spreads out, and the ferns that grow in summer reach about 1.5 m tall. Those ferns feed the crown for next year’s spears, so they need light and air. Crowded crowns compete for water and food, and the spears get thinner each year.

Laying out the bed

A bed about 1.2 m wide suits two rows of crowns 45 cm apart, with room either side to reach in for weeding and cutting without treading on the crowns. For one row, a strip 60 cm wide is enough.

Choose the spot carefully:

• Full sun, and somewhere the ferns won’t shade other crops. The north side of the plot is often best.
• Well-drained soil. On heavy clay, build a raised bed or a ridge of soil to plant on.
• Clear of perennial weeds. They’re almost impossible to get out once the crowns are in.

Planting the crowns

1. Dig a trench about 30 cm wide and 20 cm deep.
2. Make a low ridge of soil about 10 cm high down the middle.
3. Sit each crown on the ridge, about 40 cm apart, spreading the roots down either side.
4. Cover so the buds are about 10 cm below the surface, and water in.
5. Fill the trench in gradually as the shoots grow through the summer.

Plant crowns from early March to early April, and don’t let them dry out before planting.

Neighbours

Asparagus is often grown with tomatoes and parsley alongside, and kept away from onions and garlic. The companion planting checker has the full list.

Don’t cut any spears in the first year, and only lightly in the second. After that, cut for about six weeks each spring, then stop by midsummer so the ferns can build up the crowns. For planting times, see when to plant asparagus crowns.