Minnesota gardeners typically start lemongrass indoors and wait until soil reaches sixty-five degrees for outdoor planting. Knowing the best time to plant lemon grass in minnesota is key to growing this tropical herb successfully in our short, cool growing season.
Lemongrass loves heat. It cannot survive frost. In Minnesota, the window for outdoor planting is narrow but manageable with the right timing and a little planning.
Understanding Lemongrass And Minnesota’s Climate
Lemongrass is a tropical plant native to warm regions. It thrives in temperatures above 70°F. Minnesota’s climate, with its cold winters and late springs, requires careful scheduling.
You cannot plant lemongrass directly in the ground until the danger of frost has passed. The soil must be warm enough for roots to establish. Cold soil stunts growth or kills the plant.
Why Timing Matters So Much
If you plant too early, frost will kill the tender leaves. If you plant too late, the plant won’t have enough time to mature before fall frost returns. Lemongrass needs about 100 frost-free days to grow well.
In Minnesota, the average last frost date ranges from early May in the south to late May in the north. But even after frost, soil temperature is critical.
Soil Temperature Requirements
Lemongrass roots need soil at least 65°F to grow actively. Colder soil causes root rot or slow growth. You can check soil temperature with a simple thermometer.
Wait until the soil warms naturally. In most of Minnesota, this happens between late May and mid-June.
Best Time To Plant Lemon Grass In Minnesota
The absolute best time to plant lemongrass outdoors in Minnesota is from late May to early June. This window gives the plant enough warmth and time to grow before the first fall frost.
For central Minnesota, aim for the last week of May. For northern areas, wait until the first week of June. Southern Minnesota can plant a bit earlier, around mid-May, if the soil is warm.
Starting Indoors: The Smart Way
Because the outdoor season is short, most Minnesota gardeners start lemongrass indoors. This gives the plant a head start of 8 to 10 weeks.
- Start seeds or cuttings indoors 8 to 10 weeks before your last frost date.
- Use a warm location, like a sunny windowsill or under grow lights.
- Keep the soil temperature around 70°F to 75°F for germination.
- Transplant seedlings outdoors after the soil reaches 65°F.
When To Start Indoors
For a late May transplant, start seeds in early March. For early June, start in late March. This timing ensures strong, healthy plants ready for the garden.
Direct Sowing: Not Recommended
Direct sowing lemongrass seeds in Minnesota soil is risky. The growing season is too short for seeds to mature. You will get better results with transplants.
If you must direct sow, wait until soil is consistently above 65°F, usually by early June. But expect slower growth and smaller plants.
Preparing Your Garden For Lemongrass
Lemongrass needs full sun and well-draining soil. Choose a spot that gets at least 6 to 8 hours of direct sunlight daily.
Amend heavy clay soil with compost or sand to improve drainage. Lemongrass does not like wet feet.
Soil Preparation Steps
- Test soil pH; lemongrass prefers 6.5 to 7.0.
- Add 2 to 3 inches of compost and mix well.
- Ensure the planting area is free of weeds.
- Warm the soil with black plastic for a week before planting if needed.
Hardening Off Transplants
Before moving indoor plants outside, harden them off. This process takes about a week.
- Place plants outside for a few hours each day in a shaded spot.
- Gradually increase time and sunlight exposure over 7 days.
- Bring plants indoors at night if temperatures drop below 50°F.
Planting Lemongrass Outdoors
Once the soil is warm and frost danger is gone, you can transplant. Space plants 18 to 24 inches apart. Lemongrass grows into large clumps.
Dig a hole slightly larger than the root ball. Place the plant at the same depth it was growing in the pot. Water thoroughly after planting.
Mulching For Warmth
Apply a 2-inch layer of organic mulch around the plants. Mulch helps retain soil moisture and keeps roots warm. Use straw, shredded leaves, or grass clippings.
Avoid piling mulch against the stems to prevent rot.
Watering And Fertilizing
Lemongrass needs consistent moisture, especially during hot spells. Water deeply once or twice a week, depending on rainfall.
Fertilize every 4 to 6 weeks with a balanced fertilizer. Use a 10-10-10 formula or compost tea. Stop fertilizing by late August to prepare the plant for dormancy.
Extending The Growing Season
Minnesota’s fall frost can come as early as September. To get the most from your lemongrass, consider season extenders.
Using Row Covers
Floating row covers can protect plants from light frosts. They add a few degrees of warmth, allowing you to plant earlier or harvest later.
Install row covers over hoops to keep fabric off the leaves. Remove them during the day if temperatures rise above 80°F.
Container Growing
Growing lemongrass in containers gives you flexibility. You can move pots indoors when frost threatens.
Use a large pot, at least 12 inches deep, with drainage holes. Fill with quality potting mix. Place in full sun and water regularly.
Harvesting Lemongrass In Minnesota
You can start harvesting lemongrass when stalks are about 12 inches tall and half an inch thick. Cut stalks at the base with a sharp knife.
Harvest regularly to encourage new growth. Leave at least a few stalks on each plant to keep it healthy.
When To Harvest
In Minnesota, the main harvest window is from late July to early September. You can harvest until the first frost.
For the best flavor, harvest in the morning when oils are most concentrated.
Storing Lemongrass
Fresh lemongrass keeps in the refrigerator for 2 to 3 weeks. Wrap stalks in a damp paper towel and place in a plastic bag.
You can also freeze lemongrass. Chop it and store in an airtight container for up to 6 months.
Overwintering Lemongrass In Minnesota
Lemongrass is not hardy in Minnesota. You must bring it indoors before the first fall frost. Overwintering is possible with proper care.
Digging Up Plants
Before frost, dig up the entire clump. Trim leaves to about 6 inches tall. Shake off excess soil.
Pot the clump in a container with fresh potting soil. Place in a bright, cool location indoors, like a sunny window.
Indoor Care
Water sparingly during winter. Allow the soil to dry slightly between waterings. Lemongrass goes semi-dormant in low light.
Keep temperatures between 60°F and 70°F. Avoid drafts and dry air from heating vents.
Spring Revival
In early spring, increase watering and move the plant to a brighter spot. Resume fertilizing with a diluted fertilizer. By late May, it will be ready for the garden again.
Common Problems And Solutions
Lemongrass is relatively pest-free, but a few issues can arise in Minnesota.
Yellow Leaves
Yellow leaves often indicate overwatering or poor drainage. Check soil moisture and improve drainage if needed. Reduce watering frequency.
Slow Growth
Slow growth usually means the plant is too cold or not getting enough sun. Move to a warmer, sunnier location. Wait for soil to warm.
Frost Damage
If frost hits, cut back damaged leaves. The plant may recover if the roots are not frozen. Mulch heavily to protect roots.
Frequently Asked Questions
Can I Plant Lemongrass In Minnesota In July?
Yes, but it will have less time to mature. Start with large transplants and expect smaller harvests. Use season extenders to maximize growth.
What Is The Latest Time To Plant Lemongrass In Minnesota?
Plant no later than mid-June for a decent harvest. Later planting risks frost damage before the plant matures.
Do I Need To Start Lemongrass From Seed Or Can I Use Store-bought Stalks?
Store-bought stalks often root easily. Place the base in water until roots appear, then plant. This gives a head start over seeds.
How Long Does Lemongrass Take To Grow In Minnesota?
From transplant, expect 90 to 120 days to harvest. Starting indoors shortens this time significantly.
Can Lemongrass Survive Minnesota Winter Outdoors?
No. Lemongrass is not winter hardy in Minnesota. It must be brought indoors or grown as an annual.
Final Tips For Success
Lemongrass is rewarding to grow in Minnesota with the right timing. Start indoors, wait for warm soil, and protect from frost.
With a little care, you can enjoy fresh lemongrass for teas, cooking, and even natural mosquito repellent. The key is patience and planning around our unique climate.
Remember, the best time to plant lemongrass in Minnesota is late May to early June. Stick to that window, and you will have healthy, productive plants all summer.