How Do You Make Asparagus Grow Thicker? Say Goodbye to Skinny Asparagus

asparagus harvest in the backyard garden raised wooden bed

Asparagus has delicate spears and a distinct flavor. It is a favorite vegetable for many cooks. But have you ever wondered how to make those slender asparagus spears grow thicker and more robust? 

Pencil-thin asparagus looks charming. But, biting into a thick, juicy spear is so satisfying. Growing thicker asparagus makes it look better. It also gives it a better crunch and flavor. These can improve any dish it’s in. 

In this article, we cover the secrets to growing thicker asparagus. We explore many techniques and tips to help you grow your own luscious stalks in your garden or backyard.

The Importance of Growing Thicker Asparagus

Thicker asparagus spears are better for cooking. They also show a healthier, more productive plant. Growing thicker asparagus is crucial for both gardeners and culinary enthusiasts. Thicker spears are often more tender and flavorful, making them highly desirable for cooking. 

Thicker asparagus spears have a superior taste. They are also more nutritious, with higher levels of vital vitamins and minerals. These benefits make it worthwhile to invest in techniques to grow thicker asparagus. They are for anyone looking to boost their garden’s productivity and their meals’ quality.

Benefits of Thicker Asparagus

  1. Better taste and texture:
    • Thicker spears are generally more succulent and have a richer flavor compared to thinner ones.
    • They hold up better during cooking, whether grilled, roasted, or steamed.
  2. Higher Nutrient Content:
    • Thicker asparagus often contains more vitamins A, C, and K, as well as folate and fiber.
    • These nutrients contribute to a healthier diet, supporting immune function and digestion.

Understanding Asparagus Growth

grow asparagus container

Before we cover growing thicker asparagus, you need to understand how it grows. Asparagus is a perennial that can produce for up to 20 years with proper care. The first couple of years after planting are crucial for establishing a strong root system. During this time, the plant will produce thin, spindly shoots. As the plant matures, these shoots will thicken and become the succulent spears we love.

Asparagus grows from underground stems called rhizomes. Each year, these rhizomes store energy from the sun through the plant’s fronds, which are the leafy parts that grow after the spears are harvested. 

This stored energy is used to produce the next season’s spears. So, making sure your asparagus plants have strong, healthy fronds in the growing season is crucial.

Choosing the Right Varieties

One of the first steps in growing thicker asparagus is selecting the right variety. Some asparagus varieties are naturally inclined to produce thicker spears. Here are a few recommended varieties:

  • Jersey Giant: Jersey Giant is known for its large, strong spears. It is a male-dominant hybrid. It typically produces thicker and more spears.
  • Mary Washington: Mary Washington is a popular heirloom variety. It produces medium to thick spears. It is well-suited for home gardens.
  • Purple Passion: Purple Passion is visually striking with its purple spears. It also tends to have thicker stalks and a sweeter flavor.

Soil Preparation

Asparagus thrives in well-drained, fertile soil. Proper soil preparation is essential for growing thick spears. Here’s how to prepare your soil:

  1. Test Your Soil: Before planting, test your soil’s pH and nutrient levels. Asparagus prefers a pH between 6.5 and 7.5. Amend the soil accordingly to achieve this pH range.
  2. Add Organic Matter: Incorporate plenty of organic matter, such as compost or well-rotted manure, into the soil. This improves soil structure, enhances drainage, and provides essential nutrients.
  3. Ensure Good Drainage: Asparagus roots are prone to rot in waterlogged soil. If your soil is heavy clay, consider planting asparagus in raised beds to improve drainage.

Planting Techniques

Proper planting is crucial. It creates a healthy asparagus bed that yields thick spears. Follow these steps for optimal planting:

  1. Planting Time: Plant asparagus crowns in early spring as soon as the soil can be worked.
  2. Spacing: Space crowns 12-18 inches apart in rows that are 3-4 feet apart. This spacing allows each plant enough room to grow and access nutrients without competition.
  3. Planting Depth: Dig trenches about 6-8 inches deep. Place the crowns in the trenches with the roots spread out, and cover them with 2 inches of soil. As the plants grow, gradually fill in the trench with soil.
Read: Should You Let Asparagus Flower or Trim It?

Asparagus’ Fertilization and Nutrient Management

Principles of Granular Fertilizing Asparagus Beds: Feed Your Asparagus in the Spring - TRG 2015

Proper fertilization is key to growing thick asparagus spears. Asparagus is a heavy feeder, and providing it with the right nutrients will encourage vigorous growth.

  1. Balanced Fertilizer: Apply a balanced fertilizer (such as 10-10-10) in early spring before the spears emerge. Follow the manufacturer’s instructions for application rates.
  2. Top Dressing: After the harvest season, apply a top dressing of compost or well-rotted manure around the base of the plants. This will provide a slow-release source of nutrients that will support the plants throughout the growing season.
  3. Side Dressing: Side-dress in mid-summer. Use a nitrogen-rich fertilizer to support healthy fronds. Healthy fronds are essential for photosynthesis and energy storage for the next year’s spears. You may want to add coffee ground as asparagus fertilizer to raiding beds.

Watering Practices

Consistent watering is essential for growing thick asparagus spears. Asparagus plants need a steady supply of moisture, especially during the growing season.

  1. Water Deeply: Water deeply and thoroughly to encourage deep root growth. Aim for about 1-2 inches of water per week, depending on rainfall.
  2. Mulching: Add a thick layer of mulch around the plants. This will save water, stop weeds, and control soil temperature. Organic mulches like straw or wood chips are ideal.

Weed Control

Weeds compete with asparagus for nutrients, water, and light, which can hinder spear growth. Effective weed control is vital for growing thick asparagus spears.

  1. Mulching: Mulching is not only beneficial for moisture retention but also helps in weed suppression. Apply mulch regularly to keep weeds at bay.
  2. Hand Weeding: Hand weed around the asparagus plants regularly, being careful not to disturb the shallow roots. Avoid using chemical herbicides, as they can damage the asparagus plants.

Pest and Disease Management

Keeping pests and diseases under control is crucial for maintaining healthy asparagus plants. Common pests include asparagus beetles, aphids, and cutworms. Diseases like rust and fusarium wilt can hurt plants.

  1. Regular Monitoring: Inspect your plants regularly for signs of pests and diseases. Early detection is key to effective management.
  2. Natural Predators: Encourage natural predators, such as ladybugs and parasitic wasps, to help control pest populations.
  3. Organic Solutions: Use organic pest control methods, such as neem oil or insecticidal soap, to manage pests. Remove and destroy any diseased plant material to prevent the spread of disease.

Harvesting Techniques

Proper harvesting techniques can also influence the thickness of asparagus spears. Harvesting correctly ensures that the plants remain healthy and productive.

  1. Timing: Begin harvesting when the spears are about 6-8 inches tall and the tips are still tight. This usually occurs in the second or third year after planting.
  2. Method: Use a sharp knife or asparagus cutter to cut the spears at ground level. Harvest in the morning, when the spears are crisp and turgid.
  3. Duration: Harvest for a period of 4-6 weeks, then allow the plant to grow into ferns. This rest period is essential for energy storage and next year’s growth.

Long-Term Care and Maintenance

Maintaining a healthy asparagus bed over the long term involves ongoing care and attention. Here are some tips for ensuring your asparagus plants continue to produce thick spears year after year:

  1. Fall Care: In the fall, after the fronds have turned yellow and died back, cut them down to ground level. This helps prevent pests and diseases from overwintering in the plant debris.
  2. Winter Protection: In colder climates, mulch heavily in late fall. This will protect the crowns from freezing. Remove the mulch in early spring before the spears emerge.
  3. Rotation: If possible, rotate your asparagus bed every 10-15 years to reduce the buildup of pests and diseases in the soil.


Growing thick asparagus spears requires careful planning. It needs proper soil prep, consistent care, and attention to detail. By choosing the right types and good soil, and following proper planting and fertilization, you can enjoy a lot of thick, tasty asparagus. Remember, patience and perseverance are key. Asparagus is a long-term investment. It rewards diligent gardeners with years of harvests. 

Use these tips and best practices. They can change your asparagus bed into a thriving, productive garden. It will provide delicious, homegrown asparagus for years.

Similar Posts