Idaho’s arid climate and cool springs push lemongrass planting to early June, when both soil and air have warmed sufficiently. The best time to plant lemon grass in idaho is actually a narrow window that many gardeners miss. If you plant too early, frost will kill your lemongrass. If you plant too late, the short growing season won’t give you enough harvest.
Lemongrass is a tropical plant. It loves heat and hates cold. Idaho has USDA zones 3 through 7, depending on your location. Most of the state sees last frost dates between mid-May and early June. That is why early June is your sweet spot.
This guide covers everything you need to know about timing, soil prep, planting methods, and care. You will learn how to get a strong lemongrass crop even in Idaho’s challenging climate.
Why Early June Is The Best Time To Plant Lemon Grass In Idaho
Lemongrass needs soil temperatures above 60°F to grow roots. Idaho soil in May is often still cold from snow melt. By early June, the ground has warmed enough. Night temps also stay above 50°F, which is critical.
Planting in early June gives your lemongrass about 100 frost-free days. That is enough for a decent harvest. If you plant in late May, you risk a late frost. If you wait until July, you lose valuable growing time.
Here is a simple timeline for Idaho lemongrass:
- Start seeds indoors: 8-10 weeks before last frost (mid-March)
- Harden off seedlings: 1 week before planting (late May)
- Plant outside: First week of June
- Harvest: Late August through September
- First frost warning: Usually mid-October
Understanding Idaho’s Climate Zones For Lemongrass
Idaho is not one climate. The northern panhandle is cooler and wetter. The southern desert is hotter and drier. The mountains have short summers.
Southern Idaho (Boise, Twin Falls, Pocatello)
These areas are warmer. You can plant as early as late May if the forecast looks safe. But early June is still safer. Soil warms faster here because of more sun.
Northern Idaho (Coeur D’Alene, Moscow, Sandpoint)
Cooler and cloudier. Wait until mid-June. The growing season is shorter, so consider using containers that you can move indoors.
Mountain Regions (Sun Valley, McCall, Stanley)
Very short summers. Lemongrass is risky here. Use raised beds or black plastic to warm soil. Plant in early June, but be ready to cover plants if frost threatens.
How To Prepare Your Garden For Lemongrass Planting
Lemongrass is not picky about soil, but it needs good drainage. Idaho clay soil can be a problem. Here is how to fix it.
- Choose a sunny spot. Lemongrass needs full sun, at least 8 hours per day.
- Test your soil pH. Lemongrass likes 6.0 to 7.5.
- Amend heavy clay with compost and sand. Mix in 3-4 inches of organic matter.
- Add a balanced fertilizer (10-10-10) a week before planting.
- Warm the soil with black plastic if you plant in late May.
If you use containers, choose pots at least 12 inches deep. Lemongrass has big roots. Use quality potting mix, not garden soil.
Step-By-Step Guide To Planting Lemongrass In Idaho
You can start lemongrass from seed, transplants, or grocery store stalks. Each method has a different timeline.
Starting From Seed
Seeds need warmth to germinate. Start indoors 8-10 weeks before your last frost. Use a heat mat set to 70°F. Seeds take 7-14 days to sprout. Keep them under grow lights or in a sunny window.
Transplant seedlings after all frost danger passes. Space plants 24 inches apart. Lemongrass grows into big clumps.
Using Transplants From A Nursery
This is the easiest method. Buy healthy plants in late May. Harden them off for a week by putting them outside for a few hours each day. Plant in early June.
Growing From Grocery Store Stalks
Yes, you can root lemongrass from the store. Choose stalks with the bulb base intact. Place them in a glass of water for 2-3 weeks. Change water every few days. Roots will appear. Plant in soil when roots are 1-2 inches long.
This method works best if you start in April indoors. Then transplant in June.
Caring For Lemongrass After Planting
Lemongrass needs consistent moisture but not soggy soil. Idaho summers are dry. Water deeply once or twice a week, more during heat waves.
Mulch around the plants with straw or wood chips. This keeps soil cool and moist. It also suppresses weeds.
Fertilize every 4-6 weeks with a nitrogen-rich fertilizer. Fish emulsion works well. Stop fertilizing in late August so plants harden off before frost.
Watch for spider mites in hot weather. A blast of water from the hose usually controls them. Avoid overhead watering at night to prevent fungal issues.
Extending The Growing Season In Idaho
Lemongrass is perennial in warm climates, but in Idaho it is an annual. You can extend its life with these tricks.
- Use row covers or cloches in early spring and late fall.
- Plant in raised beds that warm faster.
- Grow in containers that you can bring indoors.
- Harvest stalks before the first hard frost.
- Dig up a clump and overwinter it in a pot indoors.
To overwinter, cut stalks back to 6 inches. Put the pot in a bright, cool room (50-60°F). Water sparingly. Move back outside in June.
Harvesting Lemongrass In Idaho
You can start harvesting when stalks are about 12 inches tall and thick as a finger. Cut stalks at ground level. Leave at least half the clump so it keeps growing.
Harvest in late summer for the best flavor. Idaho’s warm days concentrate the oils. Use fresh or dry for later use.
Lemongrass freezes well. Chop it and store in freezer bags. You can also dry it in a dehydrator or oven on low heat.
Common Mistakes When Planting Lemongrass In Idaho
Even experienced gardeners make these errors. Avoid them for a better harvest.
- Planting too early. Frost is the number one killer.
- Overwatering. Lemongrass likes moisture but not wet feet.
- Underwatering. Idaho is dry. Check soil often.
- Planting in shade. Lemongrass needs full sun.
- Ignoring wind. Lemongrass has tall leaves that can snap in strong wind. Plant near a fence or wall.
- Not hardening off transplants. Sudden sun and wind shock plants.
Best Varieties Of Lemongrass For Idaho
Not all lemongrass is the same. Some varieties handle cooler temps better.
- East Indian Lemongrass (Cymbopogon flexuosus): Best for cooking. Grows tall and fast.
- West Indian Lemongrass (Cymbopogon citratus): More cold tolerant. Good for Idaho.
- Java Citronella (Cymbopogon nardus): Used for mosquito repellent. Less flavorful but hardy.
Stick with West Indian for Idaho. It tolerates cooler nights and shorter seasons.
Companion Plants For Lemongrass In Idaho
Lemongrass repels some pests and attracts others. Plant it near:
- Tomatoes: Lemongrass deters whiteflies.
- Peppers: Both love heat and similar water needs.
- Basil: Repels mosquitoes and complements lemongrass in cooking.
- Marigolds: Deter nematodes and add color.
Avoid planting near fennel or dill. They cross-pollinate and reduce flavor.
Pests And Diseases In Idaho Lemongrass
Idaho is relatively pest-free for lemongrass. But a few issues can occur.
- Spider mites: Common in hot, dry weather. Spray with water or insecticidal soap.
- Aphids: Rare but possible. Blast off with water.
- Root rot: From overwatering or heavy clay. Improve drainage.
- Rust fungus: Orange spots on leaves. Remove affected leaves and improve air flow.
Most problems are preventable with proper spacing and watering.
Using Lemongrass In Idaho Cooking
Lemongrass adds citrus flavor to soups, stir-fries, and teas. Idaho’s short season means you may not get huge harvests, but even a few stalks are worth it.
Use the tender white part of the stalk. Crush it with a knife to release oils. Add to dishes whole or minced. Remove whole stalks before eating.
Lemongrass tea is easy. Steep chopped stalks in hot water for 5 minutes. Add honey or ginger for extra flavor.
Frequently Asked Questions
Can I Plant Lemongrass In Idaho In April?
No. April is too cold. Soil temps are still below 50°F. Wait until early June.
What Is The Latest I Can Plant Lemongrass In Idaho?
You can plant as late as mid-July, but harvest will be small. Early June is ideal.
Does lemongrass come back every year in Idaho?
No, it is an annual in Idaho. You can overwinter it indoors or replant each year.
How much sun does lemongrass need in Idaho?
Full sun, at least 8 hours per day. Less sun means slower growth and weaker flavor.
Can I grow lemongrass in a pot in Idaho?
Yes. Containers are great because you can move them indoors when frost threatens. Use a 12-inch pot or larger.
Final Tips For Success
Planting lemongrass in Idaho is not hard if you respect the climate. Early June is your target. Prepare soil well. Water consistently. Harvest before frost.
If you want a head start, begin seeds indoors in March. Use heat mats and grow lights. Harden off plants slowly. Then transplant in June.
Do not rush the season. One late frost can ruin your whole crop. Patience pays off with fresh lemongrass for your kitchen.
Idaho gardeners often struggle with tropical plants, but lemongrass is forgiving. Give it warmth, sun, and water, and it will reward you with fragrant stalks all summer.
Try a few plants this year. You will be surprised how well they grow. And next year, you will know exactly when to plant.