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How to Grow Mary Washington Asparagus

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Mary Washington Asparagus

Asparagus officinalis 'Mary Washington'

vegetable

Mary Washington is a classic green asparagus cultivar known for its tall, straight spears and excellent flavor. It's a perennial vegetable that produces tender shoots in spring and can remain productive for 15-20+ years with proper care. This variety is disease-resistant and widely adapted, making it a favorite for home gardeners.

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Example Mary Washington Asparagus timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Mary Washington Asparagus

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Mary Washington Asparagus

    Late summer into fall

    Before the first fall frost (≈ Nov 8)

Sample dates for Pittsburgh, PA. Sign up to get exact Mary Washington Asparagus dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 8+ hours daily for best productivity
💧
Water: Moderate water needs; keep soil consistently moist but not waterlogged. Water deeply 1-2 inches per week. Reduce watering in fall to prepare for dormancy.
📏
Spacing: 12-18 inches apart in rows spaced 4-5 feet apart (for crowns); 6-8 inches apart if growing from seed inches
📅
Days to maturity: 2-3 years from planting crowns before full harvest (year 1-2: light harvest only); 3-4 years from seed
🌱
Planting depth: Plant crowns 6-8 inches deep in trenches; cover gradually as shoots emerge. Seeds planted 1 inch deep.

Soil

Type: Well-draining loamy soil rich in organic matter
pH: 6.5-7.5
Amendments:
Compost Well-rotted manure Peat moss Aged leaf mold

Growing Zones

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Thrives in zones 3-9; best in cooler to moderate climates with distinct seasons

3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a

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Growth Stages

1

Crown Establishment (Year 1)

First growing season (spring to fall)

Young asparagus crowns develop underground root systems. Thin, weak shoots emerge in spring but should not be harvested.

Plant in early spring or fall. Keep soil moist and weed-free. Remove any flowering shoots to encourage root development. Apply 2-3 inches of mulch.

2

Root Development (Year 2)

Second growing season

The underground root system expands and strengthens. Shoots emerge in spring with slightly better vigor. Light harvest may begin mid-season.

Allow most shoots to develop into ferny foliage to feed the roots. Harvest only for 2-3 weeks maximum. Apply balanced fertilizer in spring and summer.

3

Establishment & Light Harvest (Year 3+)

Third year onward; harvest season is 6-8 weeks each spring

Mature crowns produce abundant spears in spring. Shoots are thicker and more vigorous. Plant reaches full productivity.

Begin normal 6-8 week harvest season in spring. Cut spears at soil level when 6-8 inches tall. Stop harvesting mid-June to allow regrowth for next year.

4

Fern Growth & Summer Dormancy

Late June through fall (4-5 months)

After harvest ends, remaining shoots develop into tall, feathery fern-like foliage (3-4 feet tall). Plants store energy in roots.

Do not cut ferns until after first frost. Apply mulch and maintain consistent moisture. Monitor for pests and diseases on foliage. Fertilize in mid-summer.

5

Winter Dormancy & Senescence

Late fall through early spring (5-6 months)

Fern foliage yellows and dies back as plants enter dormancy. Underground crowns rest and store carbohydrates for spring.

Cut down dead fern foliage in late fall or early winter. Apply 4-6 inches of mulch or compost over bed. Minimal watering needed.

Companion Planting

Plan your garden →

Plant with:

Parsley Basil Tomato Marigold Nasturtium Cilantro Dill

Avoid planting near:

Fennel Garlic Onion Potato Cabbage

Common Pests

  • Hand-pick beetles and eggs; spray with neem oil or insecticidal soap early in season; encourage beneficial insects; remove plant debris in fall

  • Hand-pick in early morning; use row covers during vulnerable growth periods; apply neem oil; introduce parasitic wasps

  • Select resistant varieties like Mary Washington; ensure good air circulation; remove infected fern foliage in fall; avoid overhead watering

  • Plant resistant varieties; ensure excellent drainage; rotate beds if possible; remove affected plants; sterilize tools

  • and

    Hand-pick at night; apply beer traps; use copper barriers; encourage ground beetles and other predators

Uses

🍳

Fresh cooking and gourmet cuisine

Culinary

Mary Washington spears are prized for their tender texture, mild flavor, and straight appearance. They're ideal steamed, grilled, roasted, or fresh in salads. [source]

💊

Nutritional and wellness support

Medicinal

Asparagus is rich in folate, vitamins A, C, and K, and contains glutathione, an antioxidant compound. Traditionally used to support liver function and overall health. [source]

🍳

Preservation and storage

Culinary

Fresh spears can be blanched and frozen, pickled, or canned for long-term storage. Drying is also possible for later use in soups and stocks. [source]

🦋

Perennial garden structure

Wildlife

The tall fern foliage provides habitat and food for beneficial insects, bees, and other garden wildlife. The mature plant also creates vertical interest and texture in the landscape. [source]

🏠

Cut flower arrangements

Household

The delicate fern-like foliage can be harvested and dried for use in flower arrangements, wreaths, and crafts, providing a long-lasting textural element. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Harvest spears when they are 6-8 inches tall and still tender, with tight tips. Cut or snap at ground level in the morning for best crispness. Begin harvesting in late spring of year 3, continuing for 6-8 weeks until spears become thin and spiky (signal to stop). Do not harvest in year 1; harvest lightly for 2-3 weeks in year 2. Continue harvesting annually for 15-20+ years with proper maintenance.

Fun Facts

  • 🌱 Mary Washington asparagus was developed by the USDA in the early 1900s and is named after Mary Washington, mother of George Washington, as she was known to enjoy asparagus gardening.
  • 🌱 A single asparagus plant can produce spears for 15-20+ years, making it one of the longest-producing perennial vegetables in the home garden.
  • 🌱 Asparagus has been cultivated for over 3,000 years and was a delicacy of Roman emperors, who even had a special scale called the 'libra asparagi' to measure asparagus bundles.

Gardening Terms

New to gardening? Learn about terms used in this guide:

Annual Compost Crown Cultivar Full Sun Mulch Perennial
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