Asparagus crowns should be planted at a depth that allows the growing tips or buds to be just visible or covered by a few inches of soil, with gradual backfilling as the plants grow.
Recommended Planting Depth
- Dig a trench about 20 cm (8 inches) deep and 30 cm (1 foot) wide.
- Create a ridge of soil about 10 cm (4 inches) high in the center of the trench.
- Place the asparagus crowns on top of this ridge with the growing points or buds facing upward.
- Spread the roots gently around the ridge.
- Cover the crowns with a thin layer of soil initially so that the buds are just visible or covered by about 2 inches (5 cm) of soil.
- As the asparagus grows, gradually fill in the trench with soil in layers, about 2 inches every few weeks, until the trench is filled. This gradual covering helps protect the crowns and encourages strong root development
Variations Based on Soil Type and Climate
- In sandy soils, trenches may be dug deeper (up to 12 inches) to provide better moisture retention.
- In heavier clay soils, shallower trenches (6-8 inches) may be appropriate to avoid waterlogging.
- Deeper planting tends to produce larger spears but delays spear emergence in spring because the soil takes longer to warm. Shallower planting can lead to earlier but smaller spears and more frost risk
Spacing and Other Tips
- Space crowns about 30-45 cm (12-18 inches) apart in rows spaced about 45 cm (18 inches) to 1.2 m (4 feet) apart.
- Mulch the planted area with well-rotted manure or compost to retain moisture and suppress weeds.
- Avoid planting crowns too deep initially; aim for about 5-8 inches deep total with gradual soil buildup
In summary, plant asparagus crowns about 8 inches deep initially, placing them on a soil ridge in a trench, then gradually fill in the trench as the plants grow until fully covered. This method balances protection, growth, and spear size for healthy asparagus production.
