Lemongrass Growing Zone (How to Grow Lemongrass by Zone)
Lemongrass is a tender perennial, which means that it can’t tolerate frost or very cold temperatures. Generally, it prefers a warm climate with plenty of rainfall. It’s an easy to grow plant when given the right conditions.
Lemongrass will grow as a perennial in USDA zones 10 to 11. In zones 8 and 9, it will die down over winter but come back again the following spring when the soil has warmed up. In zones 7 and below, it needs to be grown either as an annual or brought inside overwinter in pots.
Here is how you can grow lemongrass, depending on which zone you live in.
Growing Lemongrass In USDA Zones 10 to 11
Gardeners who live in USDA zones 10 to 11 can grow lemongrass outside in the garden all year round. During the cooler weather, the lemongrass will be dormant and not put on much growth.
However, once spring comes around, the lemongrass will spring back to life and grow prolifically over the warmer months. During this period, you need to ensure that you give your lemongrass plenty of water and a continuous dose of fertilizer during spring and summer.
Once winter comes around, you can slow down on the watering and fertilizing and just leave the lemongrass alone through its dormancy.
In the fall, it’s a good time to tidy up your clumps of lemongrass and remove any dead foliage. It’s also a good time to divide up your clumps if they’ve become a bit overcrowded or are in danger of taking over your garden.
At the beginning of spring, you can trim the leaves of your lemongrass plants to prune them. It’s generally recommended that you cut back around a third of the top of the leaves. This keeps your plant nice and tidy and will also encourage a growth spurt.
Growing Lemongrass In USDA Zone 8 to 9
You can still leave your lemongrass out in the garden over winter if you live in USDA zones 8 and 9. The foliage of your plant will die down, but the roots will remain viable under the soil.
To prepare your lemongrass for winter, you can either remove the dead foliage or leave it there until the spring. Whatever you choose to do, you should cover your plants with a thick layer of straw mulch.
This will keep the soil warmer and protect the tender roots in the case of a cold spell. Then in spring, pull back the mulch and remove the dead foliage if you haven’t done so already. As the soil starts to warm up, you should see some new growth coming through.
This is the perfect time to give your plant a good dose of nitrogen-rich fertilizer. Make sure that you keep your plant well watered over the warmer months and feed regularly to encourage strong growth.
The best time to divide up any large clumps of lemongrass is in early spring if you live in these zones.
Growing Lemongrass In USDA Zones 7 And Below
In USDA zones 7 or below, lemongrass will not survive through the winter as the ground will get too cold, and any frost or freezing temperatures will kill the plant. In these areas, you can grow your lemongrass as an annual and replant it every year in spring once the danger of frost is over.
Alternatively, you can dig out your lemongrass clump in the fall, divide it up and then plant it in containers that you’re going to bring indoors to protect your lemongrass from the cold.
Here’s how to do this:
- Fill some large containers with a good quality potting mix. There’s no need to add additional fertilizer at this stage because the lemongrass will be dormant over winter.
- With a sharp spade, dig up the entire lemongrass clump, making sure that most of the roots are kept intact.
- Using the same spade or a sharp knife, separate the lemongrass into individual stalks or small clumps.
- Put each of these into its own pot that you prepared earlier.
- Water well to settle the roots and let the excess water drain away.
- Once the pots are well-drained, it’s time to bring them indoors.
- As lemongrass is dormant over winter, it doesn’t require a lot of light or very much water. Therefore, you can place your pots in the garage, the basement or a room in your home. You just need to ensure that the temperature won’t drop below 50 degrees Fahrenheit (10 degrees Celsius).
- Keep an eye on your plants during winter and ensure that the soil is kept just moist.
- Once the danger of frost is over in the spring, you can start putting your lemongrass back outdoors again. However, you need to do this gradually so that the plants are fully hardened off as they’ve spent the winter out of direct sunlight.
- To harden off your lemongrass, place your pots outside during the morning where they’ll get a couple of hours of sunshine and then bring them back indoors. Increase the amount of time that your plants are out in the sun by around an hour each day until they’ve been outside all day.
Once your plants are completely hardened off, you can either continue to keep them growing in the pots that you place in a nice sunny spot, or you can plant the clumps out into the garden. Before you do this, make sure that the soil is relatively warm and that there is no danger of a late frost.
After you’ve planted your lemongrass back out into the garden, make sure that you give it a good dose of nitrogen-rich fertilizer to help stimulate new growth. Also, ensure that your plants get plenty of water during their strong growing season.
As your plants start to grow again, you’ll be able to harvest the tender, young stalks to use in your cooking. Then, it’s just a case of repeating the same process when fall comes around again.
I wrote the complete guide about growing lemongrass in cold climates, you can read it here.