A beginner’s guide to planting the best asparagus
Aspara Pacific have over 40 years of experience in breeding and growing some of the world’s tastiest asparagus. Here are our top planting tips to help guide you to getting the most success out of your asparagus patch.
When to Plant
The best time to plant asparagus is when the soil temperatures rise in the spring.
In the North Island: mid September to October and in the South Island from early October.
Planting any earlier than this may result in death of the plants due to diseases associated wet cold soils or frost damage
What To Plant
Plant healthy one year old crowns. These are the more robust than seedling, and don’t require any insecticides to control insects, where as seedlings do.
Prepare your site
Asparagus likes deep, well draining soil, free from compaction layers. Sandy loams, loamy sand or free drained volcanic soils are best.
Make sure the site is free of perennial weeds before planting.
Add plenty of organic matter (well rotted compost, mushroom compost, seaweed), into soil prior to planting.
Asparagus prefers high pH (6.0-6.5).
Lime (dolomite or hydrated lime) and superphosphate should be dug into the soil prior to planting.
Spread fertiliser on the soil surface and dig deep to bury the fertiliser to the depth that most root growth will occur i.e. 150-600 mm
How to Plant
Open a trench approximately 200 mm deep, with a flat bottom, approximately 200 mm across.
Lay the crowns down one side of the trench, 200 - 300 mm apart. Make sure the buds are facing up.
Plant another row of crowns along the other side of the trench, but in the gaps of the first row.
This gives a staggered double row with 7-10 plants per m length of row.
Cover the crowns with 5 cm of loose soil. DO NOT fill the trench with soil. This will ensure the crowns get away to a good start.
Slowly fill the trench with soil during the following summer and autumn, as you hoe any weeds on the sides of the trench.
By the following winter the trench should be filled with soil, and the soil surface flat.
How to harvest
Once the fern has completely died off in late Autumn/Winter and turned brown, cut the dead fern off at ground level. Compost or burn the dead fern
When to Harvest
If crowns grow well in the first year, in the following spring, if the spears are 15mm or greater in diameter, these can be picked, but only for a maximum of 10-14 days. This is a "bonus harvest"
Normally leave plants for two years after planting before harvesting. The first harvest season usually lasts for 3-5 weeks
Year 3 after planting, harvest for 6-8 weeks
Year 4 onwards, harvest for 8-10 weeks
Stop harvesting if the spears get thinner than 10 mm
How many crowns do I need?
Plant 7 – 10 crowns per m of row.
9 m2 = 42 - 60 crowns. This is perfect for a small family.
15 m2 = 70 -100 crowns. This will feed your family plus some for your neighbours.
100 m2 = 470 – 670 crowns.
1 acre = 14,000 crowns (Green Varieties), 16,800 crowns (Pacific Purple)