Asparagus is a perennial vegetable, so you have to wait two years after planting it to start harvesting is somewhat offset by the fact that it can produce for 15 to 30 years. However, fresh shoots that emerge from the ground in the spring can be eaten, and for the remainder of the growing season, the plant will produce tall, ferny foliage.
So, being that this plant will be in your garden for decades, it’s wise to choose the best asparagus companion plants to go with it. We’ll cover the good, and bad plants along with pests.
5 Good Companion Plants For Asparagus
Other perennials make the best companion plants.
Strawberries are one asparagus companion plant that takes up little space. Since they have different root systems than asparagus, there is little competition for nutrients, and they both produce fruit at roughly the same time of year.
In addition, they both have long lifespans.
Additional Friendly Choices
Getting Going & Starting to Plant
Asparagus prefers a location with full sun and rich, well-draining soil.
The first step in growing asparagus is to plant the crowns, but before doing so, the soil must be significantly improved with compost or other organic matter. (It only makes sense to start the asparagus plants off right because they will stay in the same bed for two to three decades.)
Work the compost as deeply as you can, 12 inches if possible (26 cm).
Plant the crowns 10 to 12 inches (26 to 31 cm) apart and 5 to 8 inches (13 to 20 cm) deep.
Make a small mound along the bottom of the planting trench after digging the planting trench. In the trench, liberally scatter bone meal or another phosphorus-rich organic fertilizer.
For better drainage in heavy clay soil, mix perlite or horticultural grit into the bottom of the trench.
Spread the roots down the sides of the mound, place the crowns on top, and then fill the trench with amended soil.
Harvesting & Growing
It takes two complete growing seasons for asparagus to establish itself.
In the first year, you shouldn’t harvest any spears. Although it’s best to avoid harvesting any in the second year, if you simply can’t wait, you can take just a few of the best and fattest spears, leaving the rest to grow into more established populations.
Asparagus spears will appear from the ground during the first two years when the soil reaches 50°F (10°C).
With a sharp knife, you can remove the new spears once they are 8 to 12 inches (20 to 31 cm) tall, about 1 inch (2.5 cm) below the soil’s surface.
Up until about mid-June, you can harvest it; however, you must let it grow naturally so that it can regenerate and prepare for the following year’s crop.
Although asparagus is a very cold-hardy plant, it can still benefit from a 3-inch (8-cm) layer of mulch in the coldest winter climates.
Bad Companion Plants for Asparagus
There are two main types of bad asparagus companion plants;
- Potatoes: Potatoes can be stunted if planted with asparagus.
- Alliums: These are plants such as onions, garlic, leeks, shallots, and chives. As these can stunt the growth of your asparagus plants.
Pests: How to Control Them
The armyworm, cutworm, aphid, and asparagus beetle are the most frequent pests of asparagus.
Annuals like marigold and alyssum will draw hoverflies and parasitic wasps to help control these pests, while perennials like lavender, thyme, and oregano can draw lacewings and damsel bugs.
Final Planting Tips
Some people who practice companion planting create perennial vegetable gardens and plant their rhubarb alongside strawberries and asparagus.
Tomato plants and asparagus are known to get along. A chemical called trichodorus (science direct.com) that the plant’s roots would release will protect the tomatoes from harming nematodes.
On the other hand, the solanine substance found in tomatoes deters asparagus beetles.
Asparagus also thrives with spinach, carrots, lettuce, or beets. You can interplant lettuce or spinach between the rows of asparagus during the first two months of the growing season.
Beets or carrots can be planted alongside early spring greens to produce a fall crop once the greens have bolted.
Dill and cosmos resemble each other in appearance and go well with asparagus. Asparagus pairs well with both basil and parsley.