Perennial vegetables that return each season without replanting offer Wisconsin gardeners a reliable harvest through challenging winters. If you’re looking for the best perennial vegetables in wisconsin, you’ve come to the right place. These plants save you time, money, and effort while providing fresh produce year after year.
Wisconsin’s climate—cold winters, warm summers, and variable rainfall—suits many perennial vegetables. Once established, they survive freezing temperatures and come back stronger each spring. Here’s your guide to picking, planting, and caring for them.
Why Choose Perennial Vegetables In Wisconsin
Perennial vegetables reduce annual garden work. You plant once and harvest for decades. They also build soil health with deep root systems that prevent erosion and improve water infiltration.
In Wisconsin, perennials like asparagus and rhubarb thrive because they go dormant during harsh winters. Their roots stay protected underground until spring warmth triggers new growth. This natural cycle means less fuss for you.
Climate Considerations For Wisconsin Gardens
Wisconsin spans USDA hardiness zones 3b to 5b. Northern areas face colder temperatures, while southern regions enjoy slightly milder winters. Choose varieties rated for your specific zone.
Most perennial vegetables tolerate zone 4 or colder. However, some need winter mulching or protection in extreme northern zones. Always check plant tags or seed packets for hardiness ratings.
Benefits Beyond Convenience
- Lower long-term costs: No annual seed or transplant purchases
- Less soil disturbance: Roots stay intact, improving soil structure
- Earlier harvests: Many perennials produce before annuals are planted
- Pollinator support: Flowers attract bees and butterflies
- Drought tolerance: Deep roots access moisture deeper in soil
Best Perennial Vegetables In Wisconsin
Now let’s explore the top choices. These plants have proven reliable for Wisconsin gardeners over many seasons.
Asparagus
Asparagus is a classic perennial that produces spears each spring. It takes two to three years to establish, but then yields for 15 to 20 years. Plant crowns in well-drained soil with full sun.
For Wisconsin, choose varieties like ‘Jersey Knight’ or ‘Mary Washington’. These handle cold winters and resist common diseases. Harvest spears when they reach 6 to 8 inches tall, but stop cutting by early July to let plants store energy.
Planting Tips
- Dig trenches 12 inches deep and 18 inches apart
- Place crowns with buds facing up, cover with 2 inches of soil
- Gradually fill trench as spears grow
- Mulch heavily in fall for winter protection
Rhubarb
Rhubarb thrives in Wisconsin’s cool springs. Its tart stalks are perfect for pies, sauces, and jams. Plants live 10 to 15 years with minimal care.
Plant rhubarb crowns in early spring. Space them 3 to 4 feet apart. They prefer full sun but tolerate partial shade. Avoid harvesting the first year to allow root establishment.
Harvesting Guidelines
- Wait until the second year after planting
- Pull stalks gently, twisting at the base
- Leave at least half the stalks to maintain plant health
- Stop harvesting by late June to let leaves regrow
- Remove flower stalks immediately to redirect energy to roots
Horseradish
Horseradish is a vigorous perennial that adds pungent flavor to dishes. Its roots grow deep and spread quickly, so contain it in a raised bed or large pot.
Plant root cuttings in spring. Space them 2 feet apart. Horseradish tolerates partial shade but produces best in full sun. Harvest roots in fall after frost sweetens them slightly.
Controlling Spread
- Use a bottomless bucket or buried barrier
- Dig up excess roots each fall
- Plant in isolated areas away from other beds
- Share extra roots with neighbors
Walking Onion (Egyptian Onion)
Walking onions produce small bulbs at the top of their stalks. These bulbs fall over and “walk” to new spots, creating a self-spreading patch. They’re extremely cold-hardy and need no replanting.
Plant bulbs in fall or early spring. They grow in any soil type and tolerate drought. Harvest green tops in spring and small bulbs in summer. Use them like scallions or pickling onions.
Sea Kale
Sea kale is a lesser-known perennial that produces tender shoots in spring. Its leaves are edible, and the flower buds taste like broccoli. It’s hardy to zone 4 and thrives in sandy soil.
Start sea kale from seed or transplants. Space plants 2 feet apart. Blanch shoots by covering them with soil or a pot to keep them tender and pale. Harvest when 6 to 8 inches tall.
Good King Henry
Good King Henry is an ancient vegetable with leaves similar to spinach. It grows 2 to 3 feet tall and produces edible flower buds. It’s extremely cold-hardy and tolerates poor soil.
Plant seeds or divisions in spring. Space them 18 inches apart. Harvest young leaves for salads or cook them like spinach. The buds can be steamed like broccoli.
Jerusalem Artichoke (Sunchoke)
Jerusalem artichokes produce edible tubers that taste like artichokes. They grow 6 to 10 feet tall with sunflower-like blooms. They’re invasive in some areas, so plant them with caution.
Plant tubers in spring, 4 inches deep and 12 inches apart. They thrive in full sun and any soil. Harvest tubers after frost sweetens them. Leave some in the ground for next year’s crop.
Managing Spread
- Harvest all tubers each year to control growth
- Plant in a contained bed or large pot
- Remove flower heads before they seed
- Dig a deep border around the patch
Planting And Care Tips For Wisconsin
Success with perennial vegetables starts with proper planting and ongoing care. Follow these steps for the best results.
Site Selection
Choose a spot with full sun (6 to 8 hours daily) and well-drained soil. Avoid low areas where water pools, as wet roots rot during winter. Test soil pH and adjust to 6.0 to 7.0 for most perennials.
Prepare the bed by removing weeds and adding compost. Perennials stay in place for years, so invest time in soil preparation upfront. Raised beds work well for drainage and root containment.
Planting Schedule
- Spring (April to May): Plant asparagus crowns, rhubarb crowns, horseradish roots, and walking onion bulbs
- Fall (September to October): Plant garlic, walking onion bulbs, and some perennial seeds
- Anytime after frost: Transplant sea kale and Good King Henry seedlings
Winter Protection
Wisconsin winters can kill unprotected perennials. Apply 4 to 6 inches of mulch after the ground freezes. Use straw, shredded leaves, or wood chips. Remove mulch gradually in spring as new growth appears.
For extra protection, cover tender plants with row covers or burlap. Snow acts as natural insulation, so let it accumulate over beds. Avoid walking on frozen soil to prevent root damage.
Watering And Fertilizing
Water deeply once a week during dry spells. Perennials have deep roots but still need consistent moisture in their first year. After establishment, they tolerate drought better than annuals.
Fertilize in early spring with a balanced organic fertilizer. Apply compost around plants each fall. Avoid high-nitrogen fertilizers, which promote leaf growth at the expense of roots and flowers.
Pest And Disease Management
Common pests include asparagus beetles, rhubarb curculio, and aphids. Handpick beetles and spray aphids with insecticidal soap. Rotate crops in different beds to reduce soil-borne diseases.
Diseases like crown rot and rust affect perennials in wet conditions. Improve drainage and avoid overhead watering. Remove infected plant parts immediately and dispose of them away from the garden.
Harvesting And Storing Perennial Vegetables
Knowing when and how to harvest ensures maximum yield and plant health. Follow these guidelines for each vegetable.
Asparagus Harvest
Harvest spears when they’re 6 to 8 inches tall and tips are tight. Cut or snap them at soil level. Stop harvesting after 6 to 8 weeks to let ferns grow and store energy for next year.
Store fresh asparagus in the refrigerator with stems in water. Use within a few days for best flavor. Blanch and freeze excess spears for winter use.
Rhubarb Harvest
Harvest stalks when they’re 12 to 18 inches long and firm. Pull them gently from the base. Never cut stalks, as this leaves stubs that rot. Remove flower stalks immediately to extend harvest.
Store rhubarb in the refrigerator for up to two weeks. Chop and freeze for pies and sauces. Do not eat the leaves—they contain oxalic acid and are toxic.
Horseradish Harvest
Harvest roots in fall after the first frost. Dig up the entire root system, but leave small pieces to regrow. Wash and peel roots, then grate or process them into sauce.
Store fresh roots in the refrigerator for several months. Grate and mix with vinegar for homemade horseradish sauce. Freeze grated horseradish for longer storage.
Common Mistakes And How To Avoid Them
Even experienced gardeners make errors with perennials. Here are pitfalls to watch for.
Planting Too Deep Or Too Shallow
Asparagus crowns need proper depth—too shallow exposes roots to frost, too deep delays emergence. Follow planting instructions precisely. Rhubarb crowns should sit just below soil surface.
Overharvesting In Early Years
New perennials need time to establish strong root systems. Avoid harvesting asparagus or rhubarb in their first year. Limit harvest in the second year to allow full growth.
Ignoring Invasive Tendencies
Horseradish, Jerusalem artichokes, and walking onions spread aggressively. Contain them with barriers or harvest all roots annually. Monitor patches and remove unwanted volunteers.
Neglecting Winter Mulch
Wisconsin winters are harsh. Without mulch, roots can freeze and die. Apply mulch after the ground freezes, not before, to prevent rodents from nesting. Remove mulch gradually in spring.
Frequently Asked Questions
What Are The Easiest Perennial Vegetables For Wisconsin Beginners?
Rhubarb and walking onions are the easiest. They need little care, tolerate cold, and produce reliably. Asparagus requires more patience but is also beginner-friendly.
Can I Grow Perennial Vegetables In Containers In Wisconsin?
Yes, but choose large containers (at least 18 inches deep) for root space. Move containers to a sheltered location in winter or wrap them with insulation. Horseradish and walking onions work well in pots.
How Long Do Perennial Vegetables Live In Wisconsin Gardens?
Asparagus lives 15 to 20 years, rhubarb 10 to 15 years, and horseradish indefinitely if managed. Walking onions and Jerusalem artichokes can persist for decades with minimal care.
Do I Need To Fertilize Perennial Vegetables Every Year?
Yes, apply compost or balanced fertilizer each spring. Perennials deplete soil nutrients over time. Regular feeding keeps plants productive and healthy.
Can I Plant Perennial Vegetables Near Annual Vegetables?
Yes, but give perennials enough space to spread without competing. Plant them at the edge of the garden or in dedicated beds. Avoid planting invasive perennials near delicate annuals.
Final Thoughts On Perennial Vegetables In Wisconsin
Perennial vegetables are a smart investment for Wisconsin gardeners. They save time, reduce work, and provide fresh food year after year. Start with a few easy varieties like rhubarb and walking onions, then expand to asparagus and horseradish.
Prepare your soil well, protect plants in winter, and harvest responsibly. With minimal effort, you’ll enjoy a productive perennial garden that thrives through Wisconsin’s challenging climate. Happy gardening.