How to grow asparagus plants
How long does it take to grow asparagus?
Before learning how to grow asparagus, you should know that planting the crop requires a lot of patience. Newly-planted asparagus plants may take 2 to 3 years to truly get started and produce, so you shouldn’t harvest it during the first couple of seasons. But once the plants have got established, you can harvest it sustainably as asparagus beds can be productive for 15, 20, sometimes up to 30 years!
You also don’t have to worry about the produce. Asparagus plants are fairly fast producers, sending up new spears every few days for a few weeks in the spring. The plant produces ½ pound of spears per foot of row in spring and early summer, so you can harvest often!
How to grow asparagus from seed
If it’s your first time growing asparagus, you can start with 5 to 10 asparagus plants (15 to 30 feet of row). To learn how to grow asparagus, make sure you start at the right time. Start seeds indoors mid-February to May under bright lights. Soil temperature for germination: 21–30ºC (70–85ºF). Planting asparagus is like a long-time investment, so you’ll want to plant the best variety available for your area.
Start by soaking the asparagus seeds for 2 hours. Plant 1 seed per 5cm (2″) pot, 1cm (½”) deep, keeping in a warm place. They can take 2-8 weeks to sprout depending on soil temperature, so you can start transplanting when the seedlings are 10-12 weeks old and danger of frost has passed.
Space 45cm (18″) apart in rows 1-2m (3-6′) apart, then place each plant in a hole 10cm (4:) deep and gradually cover the crown with soil as it grows. For thicker spears, space 30-35cm (12-14″) apart and set buds 15-20cm (6-8″) in the hole. For thinner spears, space 20-25cm (8-10″) with the buds 10cm (4″) deep.
Fertilize after harvest and again in the spring with 1-2 cups of complete organic fertilizer per 3m (10′) of row, worked in lightly. Asparagus needs 2cm (1″) of water per week. In late fall, trim ferns down to 5cm (2″) and dispose of cuttings to avoid future disease and insect problems.
Once the plants have become established and strong, at the third year you can start harvest over a 2 week period. Cut the fattest spears off at ground level when they are 15-20cm (6-10″) long. When thinner spears begin to emerge let them to grow into big fronds to nourish the roots. You can then harvest for three weeks the next year, and four to six weeks after that.