How to Plant Asparagus Roots

Preparing the Garden Bed

Buy asparagus crowns in spring. Spring is the right time to plant asparagus roots so that they have a lot of time to establish themselves before winter comes. It’s best to buy the crowns immediately before you plan to plant. If you have to wait before planting, wrap the roots in sphagnum moss to keep them healthy. You can buy sphagnum moss at a nursery or online. One-year crowns are usually better than two-year crowns, because they don’t suffer as much from the shock of transplanting.

Find a garden bed with good drainage in a sunny spot. Asparagus can last for 20 years or more, so make sure you are willing to have it where you plant it for a long time. Since asparagus doesn’t grow well with over vegetables in the same bed, find a place where it can grow by itself. A raised garden bed is a good option for asparagus. Asparagus does best in cooler places with long winters, though it can grow in most places.

Pull up all weeds and add compost. Asparagus will not be able to survive competing with other plants, so the bed should be totally empty of weeds and roots before you begin. If you think you’ve gotten all the weeds, check one more time! Add in a 2 to 4 inches (5.1 to 10.2 cm) layer of compost once the bed is all clear. If you don’t have compost, you can use manure or soil mix.

Dig a trench 6 inches (15 cm) deep and 12 inches (30 cm) wide. The length of the trench depends on how many asparagus crowns you plan on planting, so figure out how many you want to plant before you start digging. Each crown will be 18 inches (46 cm) apart. If you are digging more than one trench, space them at least 3 feet (0.91 m) apart. Dig a shallower trench in clay soil, about 6 inches (15 cm) deep.

Planting the Roots

Put a shovel of compost every 18 inches (46 cm). Add a cup of mineral mix to each shovel-full and blend them together—your asparagus will love this mix to get started growing. Once you've got it mixed, you can shape the soil into a mound about 2 inches (5.1 cm) high. Rock phosphate is a good addition to the mineral mix.

Place an asparagus crown on top of each mound. The roots should drape over the sides of the mound, and the crowns should be about 6 inches (15 cm) below the soil surface.

Add about 2 inches (5.1 cm) of soil on top of the crowns. It may seem weird to be covering them in soil, but this actually helps the asparagus grow stronger. Add another inch of soil after two weeks. Continue adding soil every now and then until it is a bit mounded.. Once you’ve got sprouts, they should be able to push through the soil that you've added.

Weed, add mulch, and water regularly. Your baby asparagus are still fragile and need your care. Mulch and weeding will help the new asparagus shoots so they don't have to compete with other plants. Asparagus evolved in swampy conditions, so they need a lot of water. Water the asparagus often, especially in the first three years of growth. In two years, you'll be able to harvest some of the tender shoots and start enjoying the fruits of your labor.