Barnacle Bill loves gardening. He provides plenty of tips and tricks for planting, harvesting, and storing quality fruits and vegetables.
Why Should I Grow Asparagus?
Asparagus spears are delightfully tasty vegetable treats that you can grow in your garden. Even though they take patience and work to cultivate, you'll quickly forget about all that and enjoy the annual harvest for many years once they're established. That's what it's all about! I'll share with you the general information you need to know to grow your own healthy greens.
Where to Grow Asparagus
In a number of regions of the United States, you can see wild asparagus growing alongside the roads. This is because if it's left alone, this hardy perennial thrives.
As far as common vegetables, I'm not aware of any other that grows wild in the same prolific manner that asparagus does. That's not to say there aren't things to be done to develop a strongly producing asparagus bed that will provide great plants year after year for you. Once they are established in a bed, they can last for up to 20 years. Some experts say they can live and produce even longer.
For the best results, growing asparagus in a place on the outskirts of the garden is ideal because of its propensity to spread.
How to Choose Your Asparagus
For a long time, asparagus options were limited because most of the most well-known varieties were female. This meant that these seeds spread out and crowded the bed, to the detriment of the plant quality. Female plants also require extra energy to produce the seed.
The new varieties recently offered to gardeners are, for the most part, male. This means these asparaguses produce a larger spear—all of their energy is put into growth rather than spread out to reproduction. They are also not partially cannibalized by the young sprouts, as their female counterparts are. When looking for asparagus varieties, ask for the male plants, as they'll produce higher-yielding, larger spears.
Because of the longevity of the asparagus, it's important to make the right decision on the particular variety because of the time it takes to establish the asparagus bed and how long they last once they're in the ground.
Another benefit of the new varieties is they are resistant to fusarium and rust while also being more tolerant to the cold than older varieties.
How to Plant Asparagus From the Seed
For a patient gardener, the option of planting asparagus from seed is tempting because it offers a wider selection of varieties. It also lets you know they are the freshest of plants.
- Wait until the soil temperature reaches about 60°F before placing the seed in the ground.
- If you choose seeds, they should be sown in a separate bed.
- Sow the seeds in a row about two inches apart and half an inch deep.
- Let them grow for a year.
- Dig the crowns up before they begin to grow and put them in the permanent bed you've prepared for them.
The majority of home gardeners will choose to grow asparagus from crowns that are a year old, not from seed.
- Be aware that planting asparagus from seed will add an additional year to the already lengthy period of time associated with firmly establishing a healthy bed of asparagus.
Read More From Dengarden
How to Plant Asparagus
When to Plant Asparagus Crowns or Plants
Once the ground can be worked in the early spring, place the asparagus plants or crowns in the soil. If you don't know what crowns are, they're buds in the center with a number of roots about the size of a pencil hanging off of them.
- If you're planting asparagus plants, place them in a trench 12"–18" wide and 6" deep. For asparagus crowns, space them about 9"–12" apart.
- Make sure to spread the roots out in a uniform manner, setting the bud side of the crown up pointing towards the surface of the soil. The crown should be a little higher than the roots of the plant.
- Immediately cover the crowns with about 2" of soil. As the summer presses on, fill in the remaining part of the trench a little at a time as the plants continue to grow higher.
- For those of you who already have an asparagus bed, you can add an inch or two of soil between the rows if the plants continue to push up when they mature.
How to Care for Asparagus
As I mentioned before, I suggest choosing a newer variety of asparagus to lower the chances of disease. Remember to buy the male varieties!
The unusually long lifespan of asparagus makes it even more important for a gardener to prepare the soil before planting. Add whatever organic materials you have to build up the soil, or buy some at the store to mix in the ground. Once the asparagus is in place, there's no way you'll be able to really change about the soil without destroying the plants and bed.
Use a balanced fertilizer for the first three years of plant growth. Apply it in the spring. In the fourth year of growth, wait until the final harvest (whenever it is in your zone) before fertilizing the ground.
You want to do this to build up the part of the plant called the fern, which stores up nutrients and energy for strong production the following year.
Caring for the Soil
The major job concerning asparagus is weeding the plants, as the spears have no foliage to shade the surrounding soil. Weeds and other competitors will inevitably sprout up, making the area look pretty sloppy. Here are my suggestions:
- Cultivate the area as early as you can in the spring once the plants emerge.
- Be sure to cultivate very lightly and continue to manage the situation.
In the fall, once the first hard frost comes, cut off the tops of the asparagus in order to help protect it against rust disease. You don't want it to lodge in the foliage of the plant.
The only insects that are going to potentially present an issue for asparagus are asparagus beetles, which are frequently found in home gardens. You can either pick them off if there aren't that many or use the appropriate insecticide.
How to Harvest Asparagus
Unless you have a huge asparagus bed, I wouldn't recommend harvesting spears until the third year after the crowns are planted. This is because asparagus sends out a horizontal root system, and it takes that long for it to be established in a way that won't hurt the plants and overall bed.
Some people would say it's okay to harvest your asparagus before that, but I wouldn't try it too much as it could do a lot of harm. The only reason it'd be okay to harvest early is if you have a big asparagus bed that's big enough to nibble some of the plants around the edges if you don't have the willpower to wait. That way, you would probably hurt only the outermost edge of the bed.
Removing too many of the spears will harm the plants, so be careful if you're grabbing a few for an early taste. Even in the third year, only harvest the plants for about a month, as their root system is still growing.
Starting from the beginning of the fourth year on, you can harvest for a period of about 2 to 4 months each year if the season lasts that long in your region.
When You're Looking to Harvest
- Look for spears that are about 5–8" in length. You can either snap the spears off or cut them. The majority of home gardeners simply snap them off.
- All you need to do is hold the spear near the base of the plant and bend it down. The plant itself will provide the right place to break, as there is fiber up higher on the plant and the weaker, fiberless part closer to the ground. This is where it'll naturally break.
- If you choose to use a knife to harvest your asparagus, you'll have to place it into the soil at the base of the plant and cut it there.
Asparagus will not last long, so be sure to use it quickly after harvesting.
The best way to store it in the short term is to treat it as you would when cutting a flower for a vase.
- Put your asparagus spears in a container along with a couple of inches of water.
- Cover it all up with a plastic bag.
- Place the asparagus in the refrigerator until you're ready to use it.
How to Grow Asparagus
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
Debbie Dakken on September 20, 2019:
When is the best time to transplant to a new area?
DavilynEversz on July 01, 2018:
Long time organic farmer here. Five years ago, ordered a lot of organic crowns. They came and they were huge. I said to myself "self, this trenching idea....no". So I didn't. I dug a hole as wide as the whole mass of crowns, put a little hill of dirt in the middle of the hole, planted it. Still bearing like crazy.
Sometimes I wonder where they get all these gardening "rules". Everyone just seems to do it without thinking. Me, always been the opposite.
Try Conovers Colossal Aspargus - its wonderful, really hearty, little maintenance, tastes wonderful.
rick natter on May 16, 2018:
most of my spears go to seed before i get a chance to pick them. my bed is 3 yrs old this year and i started with 2 year old crowns. thanks for the help. rick
Adelaide on October 15, 2017:
Should you trim or prune the asparagus ferns? If so, when? Thank you.
Cygnet Brown from Springfield, Missouri on March 27, 2014:
I love growing asparagus. Once it is established, it just grows and grows. I found that mulching my asparagus will well-aged sawdust does wonders toward keeping the weeds at bay.