A truly sustainable backyard food gardener should certainly include asparagus. It is easy to grow, fairly drought tolerant, and with just a little bit of love will return to grace your dinner table year after year.
It does, however, take a bit of initial work to plant. I should know, as I am about to plant it for the third time, sigh. The first time I followed poor advice. I created a raised bed and added a sandy soil. Since then I have learned that the sandy soil bit is great advice for a commercial effort in growing crowns from seed. The loose soil makes it much easier to dig up the crowns to sell or plant elsewhere. My poor spears grew the first year and dwindled to nothing over the next few years.
The second planting I made was next to the southeast side of my house, in ordinary garden soil. There was already an empty flower garden there, and to my mind that meant much less work. I followed the Ohio State University Extension Office advice that time. Dig the trench, add triple phosphate, toss the crowns on top, and cover with soil. This is contrary, mind you, to reams of advice I found elsewhere. Most other advice said to spread the roots out from the crown carefully, be careful not to burn the crowns with the fertilizer, and fill in the trench slowly as the young asparagus grows.
That second planting grew beautifully until my husband covered it with cement. It seems the side of the house was also the perfect place for the concrete pad for our new generator. I am truly appreciative of the natural gas generator (Really Honey, I truly am!), but it is time to revisit the Ohio State University directions for a third planting. The quick version-
1. Dig a 6 inch deep trench in well drained soil.
2. Add approximately 1 lb of triple phosphate per 50 feet of row in the trench bottom.
3. Place the crowns 1 1/2 feet apart (18 inches)
4. Replace the soil on top.
Fertilizer is important in the new bed, because the asparagus are so long lived and their roots go so deep. A properly planted bed will produce well for 15 and possibly even 20 years. The roots may be 6 or more feet into the ground, which makes it difficult to place the phosphorus the plants need at the roots at any other time. Topdressing with fertilizer or compost should also be done each year after harvest.
Harvesting more than makes up for the initial work in planting. Simply snap off the spears when they grow to about 7-8 inches high. A sharp knife will make a more asthetic cut, but the nub remaining will disappear into the soil regardless. Early in the season you will have to save the daily harvest until enough is accumulated to prepare for dinner. Mine never make it that far. They are wonderful eaten raw in the garden while dreaming of the more copious harvest warmer temperatures will bring. At some point, harvest will have to end. Stop cutting or snapping when the new spears coming up become half the diameter of a pencil. Let the new spears develop into lovely ferns. The feathery texture makes a pleasant background for marigolds or other bright annuals. Watch out for the asparagus beetle, though. If they eat too much of the asparagus fronds, there will not be as many asparagus to enjoy next year. I have found that parsley flowers will attract insects to prey on the small, black and white beetles. Organically hand pick the little critters until the second year parsely blooms.
To get the highest yield from your asparagus garden, choose a “Jersey” cultivar. These are all male plants that produce more spears instead of seeds. The 3x increase in spear production makes the “Jersey” line of plants definitely worth choosing. The yield is still higher than the new purple (also all male)cultivars, too. However, I like to include a few “Mary Washington” as well, to remind me that food blooms. The flowers are small, pretty little white bells that develop into little red seed spheres. The few seedlings that arise a year are not much of a nuisance. Even though I pull them up, they make me feel my garden is just that little more sustainable.
- Asparagus,Everything You Need to Know About (jacquesorganicgarden.com)