If you’re a Michigan gardener, knowing when to plant asparagus is the first step to a successful perennial bed. The optimal spring planting times in Michigan are crucial for getting this long-lived crop off to a strong start.
Planting at the right moment gives your asparagus crowns the best chance to establish their deep root systems before summer’s heat. In Michigan, our springs can be unpredictable, so timing is everything. Let’s break down the best schedule and methods for your garden.
When To Plant Asparagus In Michigan
For most of Michigan, the ideal window for planting asparagus crowns is in mid to late April. You should aim for when the soil is workable and has warmed to around 50°F. A good traditional rule is to plant around the same time you would plant peas or potatoes.
Planting too early in cold, wet soil can cause the crowns to rot. Waiting too long, into late May or June, gives them less time to establish before stressful summer conditions arrive. The goal is to let them settle in during the cool, moist days of spring.
Why Spring Planting is Best in Michigan
Spring planting aligns perfectly with the asparagus plant’s natural cycle. The crowns are dormant when you buy them, and cool soil temperatures signal them to begin root growth without immediately sending up spears. This focus on roots is exactly what you want.
Fall planting is sometimes discussed but is generally riskier in Michigan. Our winters can be severe and unpredictable, and newly planted crowns may not have enough time to establish and could heave out of the ground during freeze-thaw cycles. Spring is the safer, recommended season.
Understanding Your Michigan Growing Zone
Michigan spans USDA Hardiness Zones 4 through 6. This range affects your precise planting date:
- Zone 4 (Upper Peninsula & northern Lower Peninsula): Target late April to early May. Wait for the soil to fully thaw and drain.
- Zone 5 & 6 (Southern Lower Peninsula): You can often plant in early to mid-April. Use a soil thermometer to check that it’s near 50°F.
Always let soil conditions, not just the calendar, be your final guide. If spring is late and the ground is still soggy, wait another week.
How to Prepare Your Planting Site
Asparagus will grow in the same spot for 15 years or more, so site preparation is an investment. Follow these steps for the best results.
1. Choose the Right Location
Select a site with full sun—at least 8 hours of direct light daily. Good drainage is absolutely critical, as asparagus crowns will rot in standing water. Avoid low spots in your yard.
2. Test and Amend the Soil
Asparagus thrives in neutral to slightly alkaline soil (pH 6.5-7.5). Test your soil and adjust it if needed, incorporating lime in the fall before spring planting if your soil is too acidic. They prefer sandy, well-draining loam.
3. Create the Planting Bed
Remove all perennial weeds and grass from the area. Asparagus competes poorly with weeds, especially when its young. Dig a trench about 12 inches deep and 12 inches wide. Mix the excavated soil with plenty of compost or well-rotted manure.
Step-by-Step Planting Instructions
- Soak the Crowns: Before planting, soak your bare-root asparagus crowns in lukewarm water for 15-20 minutes. This rehydrates them and gives them a boost.
- Form a Ridge: In the bottom of your trench, create a small ridge of the compost-amended soil, running lengthwise down the center. This ridge will support the crowns.
- Place the Crowns: Set the crowns on top of the ridge, spacing them 12 to 18 inches apart. Drape the roots down over the sides of the ridge like an octopus on a hill.
- Cover Gradually: Initially, cover the crowns with just 2 to 3 inches of your amended soil. Water thoroughly. As the shoots grow through the summer, gradually fill in the trench with more soil until it’s level with the surrounding ground by fall.
Caring for Your New Asparagus Bed
The first two years are about building plant strength, not harvesting. Consistent care is key.
- Watering: Provide 1 to 2 inches of water per week, especially during dry spells. Deep, infrequent watering is better than frequent light sprinkles.
- Weeding: Weed meticulously by hand to avoid damaging the shallow roots. Mulching with straw or shredded leaves can supress weeds and retain moisture.
- Feeding: In early spring and again after the growing season ends, side-dress the plants with compost or a balanced organic fertilizer.
- Pest Patrol: Watch for asparagus beetles. Hand-pick them off or use an organic spray if the infestation is severe. Good garden cleanup in fall helps reduce overwintering sites.
The Patience Payoff: When to Harvest
Resist the temptation to harvest any spears in the first year. In the second year, you can harvest lightly for about 2 weeks. By the third spring, your plants are established enough for a full harvest season of 6 to 8 weeks. Stop harvesting when the spears become thin, usually around early July, and let the ferns grow to recharge the roots.
Remember, a well-cared-for asparagus bed is a decades-long asset to your Michigan garden. Taking the time to plant correctly at the optimal time sets the stage for many springs of delicious, homegrown spears. Its a true test of patience that rewards you for years.
FAQs for Michigan Asparagus Growers
What is the best asparagus variety for Michigan?
Male hybrids like ‘Jersey Knight’ or ‘Jersey Giant’ are excellent choices. They are more productive and don’t produce seeds, so they put all their energy into spear production. They are also very winter-hardy for our climate.
Can I grow asparagus from seed in Michigan?
You can, but it adds an extra year or more to the establishment process. Starting with one-year-old crowns is the most reliable and fastest method for home gardeners. Seeds require more attention and a longer wait.
How do I protect my asparagus in winter?
After the ferns turn brown and yellow in late fall, cut them down to the ground. Apply a 4-6 inch layer of mulch, like straw or chopped leaves, over the bed after the ground freezes. This helps prevent frost heaving and insulates the crowns.
My soil is heavy clay. Can I still grow asparagus?
Yes, but you must amend it thoroughly. Raised beds are a fantastic solution for heavy clay soils in Michigan. They provide the excellent drainage asparagus demands and warm up faster in spring, which can be a advantage.
If you follow these guidelines, you’ll be well on your way to a succesful asparagus harvest. The key is patience and proper initial planting—your future self will thank you for the effort you put in now.