Want to grow vegetables and take it easy? Perennial vegetables are the way to go. Supreme among the perennial vegetables is asparagus -- plant it and then reap the benefits for up to 20 years. An asparagus bed (raised or not) will produce over and over again, and you'll be dining on delicately flavored, homegrown spears you can pick just before a meal -- which might be each meal during asparagus season. Did you ever hear anyone say, No thanks, I've eaten enough asparagus this week? Preparing a bed of rich, light, well-drained soil is the foundation for this garden treasure. In our video Tricia amends the soil in one of her raised beds with organic compost and adds slow-release phosphorus and potassium. If you're planting in new ground you'll need to do some double digging -- don't run away, you only have to do this once every 20 years -- to thoroughly enrich and aerate the soil. Our video has an animation showing you how.
The Trick is in the Trench
Asparagus crowns should spread their roots in trenches. UC Davis suggests a trench eight inches deep, and the University of Missouri recommends a six inch depth. Add fertilizer or an inch of compost, then an inch of soil. Lay the roots flat on either side of the crown and cover all with two inches of soil. Keep an eye on your new plants; as they grow, add more soil so the asparagus is always under two inches of soil. Once the trench soil is level with the surrounding soil you can stop. See? Not so bad.
How to Grow White Asparagus
Still life with asparagus Adriaen Coorte c.1697 Did you know white asparagus is not a different variety from green asparagus? They grow from the same crowns. To make the stalks white, continue the soil-adding process you used to cover the new crowns. You can substitute straw for soil, if you prefer. This time you will be "hilling up" around the stalks as they grow. The stalks will stay white as long as they are not exposed to the sun. This should not be done until the asparagus is at least 3 years old.
Leo, you don’t want to plant so close to the asparagus that it gets shaded out by the other plants. I would give it room to grow. Also you need to be careful when digging in the bed to not damage any asparagus root crowns. If it is a young asparagus bed it should be ok to plant other things in it, just give it the spacing as you would for other plants.
Can you plant Tomatoes and spinach in the same bed. I have read that the depth of these plants will not intrude on the asparagus.
Susan, as long as your ground does not freeze, you should be able to plant your asparagus now. Just make sure there is good drainage and mulch heavily to avoid freezing of the crowns.
Is it too late to plant 2 yr old asparagus plants in December in Oregon 8b zone?
Rosanna, the first year of your asparagus you should let them grow and not cut them. In the fall/winter, you can cut down the ferns to the soil level. The second year you can harvest a few spears, but not too many, you are allowing the root crown to grow. The third year and beyond, you can harvest spears as normal.