Pennsylvania’s shorter growing season demands careful attention to when nighttime temperatures stay reliably above fifty degrees. Knowing the best time to plant lemon grass in pennsylvania is the single most important step for a successful harvest. Get this wrong, and your plants will struggle or die. Get it right, and you will have a lush, fragrant patch of lemon grass all summer long.
Lemon grass is a tropical plant. It loves heat and hates cold. In Pennsylvania, we have a climate that swings from freezing winters to humid summers. This means you cannot just put lemon grass in the ground whenever you want. You have to wait for the soil to warm up and the danger of frost to pass.
Most gardeners in Pennsylvania aim for a planting window between mid-May and early June. But this is not a one-size-fits-all date. Your exact location in the state matters a lot. A gardener in Erie will have a different schedule than one in Philadelphia. Let me break it down for you.
Best Time To Plant Lemon Grass In Pennsylvania
The absolute best time to plant lemon grass in Pennsylvania is after the last spring frost date for your specific area. This is when the soil temperature has consistently reached at least 60°F (15°C). For most of Pennsylvania, this falls between May 15 and June 1.
But do not just look at the calendar. Check your local weather forecast. A late cold snap can kill tender lemon grass plants. I always tell people to wait one full week after the last predicted frost. This gives the soil a chance to warm up properly.
Why Timing Matters So Much
Lemon grass is not a hardy perennial in Pennsylvania. It is treated as an annual or a container plant that you bring indoors for winter. If you plant it too early, cold soil will stunt its growth. The roots may rot. If you plant it too late, the plant will not have enough time to grow big before the first fall frost arrives.
Lemon grass needs about 100 to 120 frost-free days to reach a good size. Pennsylvania’s growing season ranges from 150 days in the northern highlands to 200 days in the southeast. So you have a decent window, but you must use it wisely.
Checking Your Local Frost Dates
Here is a simple way to find your last frost date. Use the USDA hardiness zone map or your local extension office. Most of Pennsylvania is in zones 5b to 7a. Here is a rough guide:
- Zone 5b (northern PA, like Bradford or Warren): Last frost around May 20-31
- Zone 6a (central PA, like State College or Harrisburg): Last frost around May 10-20
- Zone 6b (southeast PA, like Reading or Lancaster): Last frost around April 25-May 10
- Zone 7a (Philadelphia and Delaware County): Last frost around April 15-25
Remember, these are averages. A cold spring can push the date back by two weeks. Always watch the 10-day forecast before you plant.
Soil Temperature Is Key
Air temperature is not enough. Lemon grass roots need warm soil. Buy a simple soil thermometer. Stick it two inches into the ground. Do this at 9 AM for three days in a row. If the reading is 60°F or higher each day, you are safe to plant.
If the soil is still cold, you can warm it up. Cover the planting area with black plastic for a week before planting. This can raise the soil temperature by 5 to 10 degrees. It is a simple trick that works well in Pennsylvania’s cool springs.
Starting Lemon Grass Indoors For A Head Start
Because Pennsylvania’s spring is short, many gardeners start lemon grass indoors. This gives the plants a 6 to 8 week head start. You can plant seeds or start from stalks bought at a grocery store.
If you start indoors, do it 8 to 10 weeks before your last frost date. For most of Pennsylvania, that means starting in late February or early March. Use small pots with good drainage. Keep the soil moist and warm. A heat mat helps a lot.
Step-By-Step Indoor Starting Guide
- Buy fresh lemon grass stalks from a grocery store. Look for ones with firm, pale green bases.
- Place the stalks in a glass of water. Change the water every two days.
- After 2 to 3 weeks, roots will appear. Wait until roots are about 1 inch long.
- Plant the rooted stalks in a pot with potting soil. Bury the base about 1 inch deep.
- Keep the pot in a sunny window or under grow lights. Water when the top inch of soil feels dry.
- Harden off the plants by putting them outside for a few hours each day, starting 1 week before transplanting.
This method works well. You will have strong, healthy plants ready to go into the ground in late May.
Planting Lemon Grass Directly In The Garden
If you prefer to plant directly in the ground, wait until the conditions are perfect. The best time to plant lemon grass in pennsylvania for direct sowing is from late May to early June. But you must prepare the site properly.
Lemon grass likes full sun. It needs at least 6 to 8 hours of direct sunlight each day. It also needs well-draining soil. If your soil is heavy clay, mix in some compost or sand. Raised beds work great for lemon grass.
How To Plant Lemon Grass Outdoors
- Choose a sunny spot with good drainage.
- Dig a hole twice as wide as the root ball but no deeper.
- Mix a handful of compost into the soil you removed.
- Place the lemon grass plant in the hole. The top of the root ball should be level with the soil surface.
- Backfill with the composted soil. Press down gently.
- Water thoroughly. Keep the soil moist for the first week.
- Space plants 24 to 36 inches apart. Lemon grass grows into large clumps.
Mulch around the plants with straw or wood chips. This keeps the soil warm and moist. It also suppresses weeds. In Pennsylvania, a 2-inch layer of mulch is perfect.
Caring For Lemon Grass Through The Pennsylvania Summer
Once your lemon grass is planted, it needs regular care. The summer months in Pennsylvania can be hot and humid. This is exactly what lemon grass loves. But you still need to water it during dry spells.
Water deeply once a week if there is no rain. Lemon grass is somewhat drought tolerant, but it grows best with consistent moisture. Do not let the soil dry out completely. Also, do not overwater. Soggy soil leads to root rot.
Fertilizing For Maximum Growth
Lemon grass is a heavy feeder. It needs nitrogen to grow those tall, fragrant leaves. Use a balanced fertilizer like 10-10-10 once a month during the growing season. Or use a liquid seaweed spray every two weeks.
If you prefer organic methods, side-dress with compost or aged manure. Apply a 1-inch layer around the base of the plants in June and again in July. Water it in well.
Dealing With Pests And Problems
Lemon grass is relatively pest-free in Pennsylvania. But you might see spider mites or aphids during hot, dry weather. A strong spray of water from the hose usually knocks them off. If not, use insecticidal soap.
One common problem is yellowing leaves. This is often a sign of overwatering or poor drainage. Check the soil. If it feels wet and muddy, let it dry out before watering again. Also, make sure your planting site drains well.
Harvesting Lemon Grass In Pennsylvania
You can start harvesting lemon grass when the stalks are about 12 inches tall. Cut the stalks at ground level using a sharp knife. Leave at least 2 inches of the base so the plant can regrow.
Harvest regularly to encourage new growth. The more you cut, the more the plant produces. In Pennsylvania, you can harvest from July until the first fall frost. That gives you about 3 to 4 months of fresh lemon grass.
When To Stop Harvesting
Stop harvesting about 4 weeks before the first expected frost. This gives the plant time to store energy for winter. If you are growing lemon grass as an annual, you can harvest everything before the frost kills it.
The first fall frost in Pennsylvania usually occurs between late September (northern areas) and mid-October (southern areas). Check your local frost dates. Plan to dig up or harvest all lemon grass by that time.
Overwintering Lemon Grass In Pennsylvania
Lemon grass will not survive a Pennsylvania winter outdoors. But you can overwinter it indoors. This is a great way to save your plants for next year. You have two options: bring the whole pot inside, or dig up a few stalks.
If your lemon grass is in a container, move it indoors before the first frost. Place it in a sunny window. Water sparingly through the winter. The plant will go semi-dormant. It may look a bit sad, but it will bounce back in spring.
If your lemon grass is in the ground, dig up a few healthy stalks. Trim the leaves down to about 6 inches. Plant them in a pot with potting soil. Keep them indoors in a bright spot. Water just enough to keep the soil from drying out completely.
Tips For Successful Overwintering
- Check for pests before bringing plants indoors. Rinse the leaves with water.
- Place the pot in a south-facing window for maximum light.
- Do not fertilize during winter. The plant is resting.
- Water only when the top inch of soil is dry. Overwatering is the biggest killer.
- In early spring, move the pot to a brighter spot and start watering more. New growth will appear.
By following these steps, you can keep your lemon grass alive for many years. It will get bigger and better each season.
Common Mistakes To Avoid
Even experienced gardeners make mistakes with lemon grass in Pennsylvania. Here are the most common ones and how to avoid them.
- Planting too early: Do not rush. Cold soil kills roots. Wait until soil is 60°F.
- Planting in shade: Lemon grass needs full sun. Partial shade leads to weak, leggy growth.
- Overwatering: Lemon grass likes moisture, but not wet feet. Good drainage is essential.
- Ignoring frost warnings: A single frost can kill your plants. Be ready to cover them or bring them inside.
- Not harvesting enough: Regular harvesting keeps plants productive. Do not let them get too tall and woody.
Avoid these mistakes, and you will have a great harvest.
Best Lemon Grass Varieties For Pennsylvania
Not all lemon grass varieties are the same. Some are more cold-tolerant than others. For Pennsylvania, I recommend these varieties:
- East Indian Lemon Grass (Cymbopogon flexuosus): This is the most common type. It grows well in Pennsylvania summers. It has a strong lemon flavor and aroma.
- West Indian Lemon Grass (Cymbopogon citratus): This variety is slightly less cold-hardy. But it grows fast and produces thick stalks. It is great for cooking.
- Citronella (Cymbopogon nardus): This is the mosquito-repelling type. It grows well in Pennsylvania but is not as good for cooking. It has a stronger, more medicinal scent.
All of these varieties will grow in Pennsylvania if planted at the right time. Choose based on your needs. If you want lemon grass for tea and cooking, go with East Indian or West Indian. If you want to repel mosquitoes, go with citronella.
Using Lemon Grass From Your Garden
Once you have a good harvest, you can use lemon grass in many ways. It is a staple in Asian cooking. Use the tender inner parts of the stalks in soups, curries, and stir-fries. You can also make tea by steeping chopped leaves in hot water.
Lemon grass is also great for making infused oils and vinegars. Chop the stalks and add them to a bottle of olive oil or vinegar. Let it sit for two weeks. Strain and use it for salad dressings or marinades.
If you have more lemon grass than you can use, freeze it. Chop the stalks into small pieces. Put them in a freezer bag. They will keep for up to six months. You can also dry the leaves for tea.
Frequently Asked Questions
Can I plant lemon grass in Pennsylvania in July?
It is possible, but not ideal. July is late. The plant will not have enough time to grow large before frost. If you must plant in July, use a large pot that you can bring indoors later.
What is the best time to plant lemon grass in Pennsylvania for containers?
For containers, you can plant a few weeks earlier than in-ground. You can move the pot indoors if frost threatens. Aim for early May in most of Pennsylvania. Just watch the weather.
Does lemon grass come back every year in Pennsylvania?
No, not outdoors. Lemon grass is a tropical perennial. It will die if left outside in winter. You must overwinter it indoors or treat it as an annual.
How do I know if the soil is warm enough for lemon grass?
Use a soil thermometer. Insert it 2 inches deep. If the reading is 60°F or higher for three consecutive mornings, the soil is warm enough.
Can I grow lemon grass from seed in Pennsylvania?
Yes, but it is slower than starting from stalks. Start seeds indoors 8 to 10 weeks before the last frost. Germination can take 2 to 3 weeks. Keep the soil warm and moist.
Final Thoughts On Planting Lemon Grass In Pennsylvania
Planting lemon grass in Pennsylvania is not hard once you understand the timing. The best time to plant lemon grass in pennsylvania is after the last frost, when soil is warm. For most of the state, that means mid-May to early June. Start indoors for a head start. Use containers if you want to extend the season.
With a little planning, you can enjoy fresh lemon grass from your garden all summer. It adds a wonderful flavor to your cooking and a tropical feel to your yard. Just remember to bring it indoors before the first frost. Your lemon grass will thank you.
Now go ahead and check your local frost dates. Get your soil thermometer ready. And get ready to plant some lemon grass. It is one of the most rewarding herbs you can grow in Pennsylvania.