Asparagus is a divisive vegetable, with people either passionately adoring its unique flavor and nutritional benefits or strongly disliking its very existence. As someone who falls into the former category, I’m thrilled to share my enthusiasm for this perennial favorite. Not only does it pack a punch in terms of vitamins A, C, K, folate, iron, copper, and fiber, but its versatility makes it a staple in many kitchens.
That being said, I’ve noticed that those who claim to dislike asparagus often have a broader distaste for healthy, delicious vegetables. Alternatively, they might be sensitive to the compounds responsible for asparagus’s pungent aftereffects – asparagusic acid. This substance, which breaks down during digestion, can release sulfurous elements into urine, leading some people to describe it as an overpowering ‘Eau d’asparagus.’ For others, however, this peculiar phenomenon is hardly noticeable.
Assuming you’re reading this and share my affection for asparagus, I’m happy to report that cultivating this beloved vegetable is relatively straightforward. Asparagus can thrive in nearly any climate, from the sun-kissed fields of California to the tropical islands of Hawaii – provided it enjoys a period of cold winters.
Unfortunately, its popularity extends beyond human circles; many wildlife species also have a taste for asparagus, making it essential to take precautions to protect your homegrown harvest.
Quick Gardening Facts for Asparagus:
For a thriving asparagus crop, you’ll want to consider the plant’s hardiness zones (3-9) and ideal soil conditions, with a pH between 6.5 and 7.5 and good drainage. Full sun is also essential. When it comes to planting, start indoors 6 to 12 weeks before the last frost date in spring or 4 to 6 weeks before the first frost date in fall. Allow for 1 to 2 weeks of hardening off before transplanting, and then move them outdoors 12 to 14 days later.
Space plants 12 to 15 inches apart and rows 2 to 4 feet apart, with a seed depth of ¼ to ½ inch and 8 to 10 inches for seedlings. Asparagus has several beneficial companion plants, including tomato, basil, parsley, grape, beet, lettuce, spinach, dill, coriander, comfrey, rhubarb, and strawberry. On the other hand, avoid planting with onion, garlic, or potato, as they can be detrimental to your crop. To keep your asparagus healthy, water them heavily every 10 to 14 days.
Apply a fertilizer rich in potassium and phosphorus before planting and one rich in nitrogen afterwards. For the first year’s beds in autumn, use compost manure to give your plants a nutrient boost. As with any plant, there are potential problems to watch out for, including asparagus beetle, phytophthora crown and spear rot, cercospora blight, asparagus rust, and fusarium wilt. Finally, harvest your asparagus when the plants reach 6 to 8 inches high and the spheres are ⅜ inch thick.
Best Asparagus Varieties to Plant
While sowing asparagus seeds can be a thrilling venture, many enthusiasts opt for a more straightforward approach by starting with readily available crowns. The likes of Mary Washington, Jersey Knight, and Purple Passion are popular choices that require minimal effort to get started. However, the allure of varieties like Precoce D’Argenteuil, renowned for their blanching capabilities, might just tempt some to take on the challenge of growing from seed.
Mary Washington
Mary Washington, an heirloom asparagus variety, stands out for its impressive productivity and natural resistance to diseases. Growing this variety can be a highly rewarding experience, especially for beginners. One of its notable characteristics is that it produces slender spears, which are more prone to becoming stringy if not harvested at the optimal time. Moreover, these spears tend to quickly develop their fern-like foliage in warm weather conditions.
Jersey Knight
The Jersey Knight hybrid asparagus variety boasts predominantly male plants, which yield slightly larger and more resilient spears that retain their tenderness for a longer period before transitioning into ferns. While the older spears may become less palatable, regular harvesting during the peak season will ensure optimal flavor and texture.
Purple Passion
While Jersey Knight may have a slight edge in terms of productivity, Purple Passion still offers some compelling advantages. The striking purple spears it produces are undoubtedly a visual treat. One notable difference between Purple Passion and other varieties is its shorter lifespan – typically around 10 years compared to 30 for Mary Washington. Additionally, hybrids like Purple Passion tend not to produce as many self-seeded plants as their non-hybrid counterparts do.
Furthermore, hybrid offspring may not always produce true-to-form results. However, it’s worth noting that Purple Passion grows exceptionally well in a wide range of soil types.
How to Plant Asparagus
Asparagus is renowned for its remarkable perennial nature, with well-maintained plants capable of thriving for a decade or more. This hardiness extends to heirloom varieties, which possess the unique ability to self-seed and propagate in situ, even if the original plants succumb to natural aging. With proper care, it’s possible to cultivate asparagus in the same location indefinitely.
However, once established, these plants can be notoriously difficult to relocate without significant effort, making careful selection of their growing site crucial.
Choose the Right Site
When selecting a spot for your asparagus patch, prioritize areas with good drainage, wind protection, and at least 6-8 hours of direct sunlight daily. In hot climates, it’s beneficial to have afternoon shade to mitigate the intense summer heat. Additionally, consider sites that provide some reprieve from the scorching sun during peak hours. Most herbivores and omnivores are attracted to asparagus, so a well-fenced garden or area with low pest pressure is crucial for successful cultivation.
Temporary fencing or netting can be an effective deterrent during the spear-growing season (spring and fall) to promote healthy plant establishment and ultimately, a bountiful harvest. However, if you’re dealing with prolific diggers like rabbits and voles, a more substantial underground barrier of at least 2 feet is necessary to safeguard your asparagus plants.
How Much Space?
To determine the ideal space allocation for growing asparagus, it’s essential to consider several factors. Start by calculating how much space is needed to accommodate the recommended 12-18 inches of separation between each plant. This will also leave room for you to easily access and harvest your crops without feeling cramped. It’s also important to consider the specific climate conditions in your area.
In drier regions, closer plantings can be tolerated, while humid environments may require wider spacing to prevent fungal diseases from taking hold.
How many plants do you need?
When cultivating asparagus, it’s essential to consider the spacing and soil requirements. On average, a single healthy plant can produce around 4 pounds of spears starting from the fourth year of growth. For a bountiful harvest of 10 pounds per year, you would need approximately 25 plants. This means dedicating about 25 feet of your garden bed to asparagus with 12 inch spacing, or roughly 33 feet with 16 inch spacing.
It’s worth noting that this level of space demands significant soil preparation and maintenance, which can be a considerable investment for small gardens.
Planning Your Asparagus Patch
Many gardeners begin their asparagus patch with a manageable number of plants, such as ten or twelve, and gradually expand it over time. Another approach is to plant in patches rather than linear rows. For instance, you could create a 10×10 plot, allowing for greater flexibility and ease of maintenance. In well-draining soil with moderate moisture levels, you can space your plants 12 inches apart, with two feet between each row.
This configuration enables you to fit 40 plants within a 100-square-foot area. With more extensive soil preparation and the addition of rich compost, such as 4-6 inches of fresh material, you could potentially accommodate 60 plants in this same space.
Soil Preparation for Asparagus
Before planting asparagus, it’s crucial to prepare the soil properly. Unlike many plants that can thrive in various soil types, asparagus requires specific conditions to produce a bountiful harvest. A well-prepared soil bed is essential for optimal growth and yields. For traditional growers, the process typically involves digging six-inch trenches, placing asparagus crowns within them, and backfilling with a mixture of two inches of compost and original soil.
If you’re lucky enough to have good soil from the start, this approach can yield satisfactory results. My personal method takes a slightly different approach. I dig a trench approximately one foot deep and wide enough for my shovel (roughly one foot). Next, I blend native soil with about half as much compost. Given our heavy clay terrain, I need to manually break up any stubborn clumps that emerge during the mixing process.
Once the mixture is prepared, I backfill it with six inches of the blended soil and compost. This creates a loose, nutrient-rich environment for the asparagus to establish itself. It’s essential to maintain a soil pH between 6.5 and 7.5 for optimal asparagus growth. If you’re unsure about your soil pH, consider conducting a test to determine whether lime or sulfur products are necessary to adjust the pH accordingly.
Planting Your Asparagus
Starting an asparagus garden can be a bit of a wait, but with the right approach, you can enjoy this delicious perennial for years to come. One option is to begin from seeds in a greenhouse or protected area, although it may take around 5 years before you start harvesting. Alternatively, you can purchase established plants, which can be more challenging to find. The most common method of planting asparagus is using dormant two-year-old crowns, which often come in bags of three to six.
This approach is ideal for beginners and will be the focus of this discussion. While it’s technically possible to plant asparagus at any time the soil can be worked, early spring or fall are generally considered the best times to do so. Soil temperatures above 50°F, air temperatures above 40°F, and regular rainfall all contribute to successful establishment. Planting asparagus is similar in many ways to planting potatoes.
Once you’ve decided on your soil preparation method and gathered your materials, plant your crowns about 6 inches deep, setting the roots firmly into the soil like placing a crown on a head. Cover with an initial 2-3 inches of soil mix. In addition to the standard soil cover, I personally like to add a layer of hay from my goat barn (complete with bonus urine and manure for added fertility) to help retain moisture until the plants grow in.
Once the asparagus tips begin poking through, backfill your trench with more soil, adding additional hay or straw if you have it. Repeat this process until all the soil is backfilled to grade level. Finally, be sure to water deeply at planting time and keep the soil consistently moist until it’s back up to grade.
Test-Drive Your Asparagus Growing Skills
If you’re looking to test the waters before fully committing to growing asparagus, consider planting a bag of crowns near your existing landscaped areas with similar pH requirements. For instance, plant them under deciduous flowering trees or near other suitable spots outside the shade line. This approach allows you to gauge the success and ease of growth without making a large commitment.
To get started, dig a one-foot diameter hole and create a deep crater.
Then, fill the entire hole with compost instead of soil. Begin by adding six inches of compost, followed by placing your crown, and finally cover it with two more inches. Mark the spot with a stake until the plant parts are visible.
As spears emerge, continue to backfill with compost until you reach grade level. Next, top it off with mulch and maintain the area as you would any other landscaped space (e. g., regular watering, feeding, and weeding).
Once you’ve had a taste of growing asparagus in your existing landscaping, I suspect you’ll want to expand. In that case, simply refer back to these instructions to start your own patch!
How to Care for Asparagus
After asparagus spears emerge, it’s essential to establish a consistent watering routine. Aim to provide about an inch or two of water per week during dry spells. As the fern-like foliage grows, it plays a crucial role in harnessing sunlight and supporting deep root development. During the initial two years following planting, refrain from harvesting the tender shoots. Instead, allow them to mature into full-size plants, leaving them standing until they naturally die back over winter.
If you don’t experience natural die-off, prune older ferns as soon as signs of aging appear – such as browning tips or partial dieback – to make way for new growth. Weeding is vital for successful plant establishment, and once your asparagus plants have developed substantial above-ground mass, consider adding a few inches of mulch to simplify maintenance and retain soil moisture. To promote healthy growth and continued production, supplement with regular applications of fertilizers.
This can be achieved through the use of compost tea, fresh compost, or worm castings. Aim to add a couple of inches of compost annually to keep your asparagus thriving.
Common Problems with Growing Asparagus
While we’ve emphasized the significance of utilizing effective fencing methods for pest control purposes, such as deterring digging animals like voles or nibbling creatures like deer and chickens, it’s equally crucial to acknowledge the presence of insects that specifically target asparagus. These unwanted visitors can significantly impact your crop’s growth and yield, making it essential to develop a comprehensive strategy to manage them effectively.
The Common Asparagus Beetle
The Common Asparagus Beetle is one of the most significant pests affecting asparagus plants, characterized by its reddish body and distinctive black and white cross-like markings on its back. This beetle can wreak havoc on your asparagus patch, causing damage to leaves, stems, and even spears, if left unchecked. If you notice bent spears, damaged stem tips, or fronds with holes, it may be a sign that the Common Asparagus Beetle is feeding on your plants.
The key to managing this pest is manual control: regularly inspect your asparagus for adult beetles during the afternoon when they’re most active, and manually remove them along with their eggs from the spear tips. Eggs are small, oval-shaped, and parallel to the spearhead. While neem oil can provide temporary relief, daily manual control remains the most effective approach.
For severe infestations, chemical controls like carbaryl, malathion, and permethrin may be necessary, but always follow package labels for guidance.
The Spotted Asparagus Beetle
While ladybug look-alikes might seem harmless, the spotted asparagus beetle is a sneaky culprit that can cause significant damage to your crops. Its elongated body and similar spots make it easily overlooked in an asparagus bed. Unlike its more destructive counterpart, this beetle primarily targets spear tips, rendering them less appealing. Additionally, it feasts on seed pods, making harvesting a challenge.
As if insect damage wasn’t enough, it can also create an environment conducive to Fusarium-related fungal disorders, ultimately threatening the health and productivity of your plants. To prevent serious harm, regular manual inspections and removal of these pests, along with their larvae, are crucial. For added protection, mild pesticides like neem oil or Diatomaceous Earth can provide temporary relief.
In severe infestations, a combination of insecticidal soap and permethrin-based insecticides may be necessary to safeguard your crop.
Crown Rot and Root Rot (Fusarium)
Two primary forms of Fusarium, a fungal disorder that can ravage an asparagus patch, are commonly referred to as crown rot or root rot. These disorders can significantly impact production, causing wilt, browning of plant parts, and limiting the plant’s ability to absorb essential nutrients. While there is no definitive treatment for these fungal infections, it’s essential to recognize that damaged asparagus plants are more susceptible to infection.
Additionally, humid conditions can exacerbate the likelihood of infection occurring. By adopting a proactive approach to plant care, including regular monitoring, prompt removal of pests, and providing ample space between plants, you can mitigate risks and maintain healthy, thriving asparagus plants.
Best Companion Plants for Asparagus
When it comes to deterring asparagus pests, companion planting is a highly effective strategy. Certain plants have natural properties that repel or confuse common asparagus pests, making them ideal neighbors for your prized asparagus patch.
For example, tomatoes and parsley are known to keep these unwanted visitors at bay, while basil, lettuce, marigolds, nasturiums, flowers in the Aster family, beets, and spinach can also provide a welcoming atmosphere for your asparagus without compromising its growth or quality.
Worst Companion Plants for Asparagus
When cultivating asparagus, it’s essential to be mindful of the surrounding plant life. Certain vegetables can actually hinder its growth or create an unfavorable environment. Some plants that may not thrive when planted alongside asparagus include garlic, onions, and potatoes. These vegetables seem to have a less-than-ideal coexistence with asparagus, so it’s best to keep them separate.
How to Harvest Asparagus
After dedicating three years to nurturing asparagus, it’s tempting to harvest sooner rather than later. However, for optimal results, wait until year four when spears are at their best. That being said, if you’ve taken exceptional care of your plants and experience a spear explosion in year three, you can safely harvest 10-30% of your crop without compromising the long-term health of your asparagus patch.
In subsequent years, provided your plants continue to thrive, you’ll be able to harvest all your spears as they emerge for several weeks. Keep in mind that once production slows and spears become thinner, it’s essential to stop harvesting and allow them to reach their full size. When the time comes to harvest, use a sharp knife to cut the spear at ground level when it reaches approximately 8 inches in height. Thicker spears might require shorter harvesting for the best flavor.
During peak growing season, daily checks are necessary to ensure timely harvesting before spears start to fern. To minimize risks associated with pruning or cutting, it’s crucial to cut at an angle so that rainwater runs off the cut part, reducing fungal risks and rot. Asparagus is typically enjoyed fresh (raw or cooked) or lightly blanched and frozen for future use. If overnight storage is necessary, store your asparagus in a cup of water in the refrigerator for the freshest taste.
Alternatively, wrap a bunch in a moist paper towel and store it in the crisper for several days. Ultimately, there’s no denying that fresh-as-picked-from-the-garden asparagus is unbeatable. If you’re willing to put in the effort to grow your own, you deserve to savor the peak flavor and texture of your hard-earned crop.
Is Asparagus Worth all this Work?
Growing asparagus may require an initial investment of time and effort, but it’s a worthwhile endeavor. Unlike annual vegetables, which demand similar levels of soil preparation and maintenance, asparagus offers a unique advantage: once established, it becomes a low-maintenance crop that provides bountiful yields for years to come. No more worrying about saving seeds, starting new plants, or dealing with uncertain germination rates.
With a little TLC – think weeding, watering, and composting – your asparagus patch will thrive and reward you with delicious returns. So, fellow asparagus enthusiasts, take the plunge and cultivate some of this tasty perennial in your own backyard!
