Asparagus is one of the all-time great perennial vegetables. A member of the lily family, asparagus is a sure sign of spring as soon as spears appear. The biggest keys to successful asparagus growing? Plenty of planting space and plenty of patience.
How to Grow Asparagus
Take time to think about where you want to place your permanent asparagus bed, because plants can live 10 years or more. Locate the bed in a sunny spot, assuring grown plants won’t block the sun from other parts of the garden.
You’ll also need to consider how much asparagus you’ll want to eat; plan for about 10 plants per person to make sure there’s enough of this vegetable to go around. Most asparagus varieties are green but there are white and purple varieties, too.
- Start in early spring and amend the asparagus bed with compost and dig in a high phosphorus and potassium fertilizer. Plants grow best in a well-drained, sandy loam.
- Dig a flat-bottom trench that’s 12-15 inches wide and about 8 inches deep; rows should be at least 24 to 36 inches apart.
- Select transplants that are 1 or 2 years old; each should have at least 2 clusters of buds.
- If you decide to plant from seed, start asparagus seeds indoors 12 weeks before planting. Allow 3-4 weeks for seeds to germinate.
- Wait to plant until the danger of frost has passed and the soil warms to 55-75 degrees.
- Spread roots of transplants out radially like a wheel and cover with 1-3 inches of soil.
- After shoots appear, cover with several more inches of soil.
- Continue adding soil in small amounts as the shoots grow, until you’ve filled in the original trench.
- Help plants get established quickly over the first two seasons by watering regularly and deeply. Don’t let the asparagus bed dry completely.
- Keep asparagus bed weed-free with a thick layer of organic mulch; handpick any weeds that show up.
- Sidedress plants with fertilizer in early spring.
- Asparagus planted as transplants will be ready to harvest lightly the second year; started from seed wait until the third or fourth year.
- Harvest slightly more spears each season to help extend the length of the harvest.
- Cut spears at soil level when they’re about 8 inches long with tight tips.
- It’s important to allow some spears to remain in the garden produce leaves and make food to store in the roots. Pencil-thin spears are a signal to stop harvesting because food stores are almost exhausted.
- Sidedress with fertilizer after the harvest to encourage good asparagus growth next season. An added step is to top-dress the bed with well-aged manure.
Plant asparagus with these companions:
Avoid planting garlic, onions or potatoes in close proximity to the asparagus bed.
Materials for Success
- High-quality compost or composted manure
- 5-10-10 fertilizer
- Companion plants
- Drip irrigation tubing or soaker hose
To learn more about growing artichokes or about growing your own edible vegetable garden, contact the pros at Nick’s Garden Center.