How to grow backyard asparagus that produces for years

Living in Utah, it’s a little bit tricky to successfully grow asparagus in your home garden. But, after lots of trial and error, we figured out some fool proof tricks. With a little bit of time and patience, you’ll be eating backyard asparagus for dinner. Check it out!

Freshly cut stalk of asparagus from the garden — *Freshly cut spear of asparagus. This is a hardy perennial.*

Asparagus is one of those fancy vegetables that are super delicious and healthy but kind of expensive. At about $5 per pound in the grocery store, it’s not something most people buy everyday. But since we love asparagus, we worked hard at figuring out the best way to grow it in the Midwest, specifically in Utah. Now is is the best time to start a vegetable garden and plant this perennial crop. Here’s how you can do it yourself.

Soil preparation for planting asparagus

Find a spot in your garden that has well-drained soil and has full sun. Asparagus grows best in sandy soil. Also, asparagus is a perennial vegetable and doesn’t need to be replanted each year. So you never till it up. That means you need to find a permanent spot in your garden.

Dig a deep trench (12- to 18-inches) where you will be planting your asparagus and fill the bottom of the trench with compost, potting soil, ash and any other nutrients. We have heavy clay soil so we wanted to create a spot with good drainage and encourages good root growth. You can get a soil test to determine your soil ph and the fertilizer needs of your garden. Follow the recommendations on your test results. Our row of asparagus is on about 20 feet of row and that produces more than enough asparagus for our family of seven every year.

Row of asparagus in our garden — *Our 20-foot row of asparagus in our backyard garden.*

Plant your asparagus seeds

We tried planting asparagus roots or asparagus crowns and they all ended up dying. So, we went with seeds instead. However, the asparagus seeds at the store aren’t very good. We bought some asparagus seeds online instead. Mary Washingtons are a popular variety and a good choice. They germinated and grew well.

Plant seeds 12 inches apart about 1/2″ deep. You can also plant the seeds in pots about 8-10 weeks prior to the last frost and then transplant them. You’ll want to water your seeds daily until they germinate and you see them popping up. It can take about 8 weeks so just be patient.

Watering and fertilizing your asparagus plants

It’s really easy to over water asparagus if you’re not careful. We use drip irrigation because it waters more evenly and consistently. Aim at watering 1-2 inches every other week for the first two years. You can also lay out some mulch over the asparagus for adequate soil moisture and for weed control. At year three, you can reduce watering to every three weeks.

You can fertilize your asparagus after the harvest is over around early June. Use a complete fertilizer, similar to the fertilizer that you use for your lawn.

Establish your asparagus

The biggest mistake people make with asparagus is they get impatient and harvest the spears too early. It takes at least two solid years before you can cut any of the spears. This is because the asparagus needs time to establish a large roots system. So, even when you see new shoots, just leave them there for the first year and second year. It takes a long time.

They will eventually grow big and tall into ferns which you will leave until they die in the fall. Then, at that point, mow the ferns with a lawn mower and scatter the clippings from the ferns as mulch back onto the asparagus patch. Do NOT till up your asparagus.

Harvesting your asparagus

On the third year after planting your asparagus seeds, you can finally harvest your fresh asparagus in early spring and eat them. Yay! Harvest spears that are about 9 inches tall. Only harvest thick spears that are as thick as your pinky finger. Cut them at ground level with a sharp knife. If they are really thin, leave those uncut in the ground.

Asparagus harvesting season schedule

Year 1 & 2: Do not harvest
Year 3: Harvest for 4 weeks
Year 4: Harvest for 6 weeks
Year 5+: Harvest for 8 weeks

Harvesting season is over when you starting seeing fewer spears and most of the spears are smaller than the diameter of a pencil. In most areas, this will be around mid-June.

Harvest asparagus spears when they are 9-12 inches tall and thicker than a pencil — *Harvest backyard asparagus spears when they are 9-12 inches tall and thicker than a pencil*

After-harvest care for asparagus

Follow the same after-harvest care that you follow while your asparagus is establishing. Let the remaining spears grow to ferns and during late fall, mow them down and scatter the clippings on the asparagus bed as soil mulch. You can expect to receive a consistent harvest of asparagus year after year for about 15 years! Yum! If you have a problem with asparagus beetles, use a pesticide labeled for this pest.

Here’s a video of my husband explaining homegrown asparagus.