The lemon tree (botanical name *Citrus x limon*) is a total fan favorite for home gardeners. Not only does it bring those breezy Mediterranean vibes to your space, but it also rewards you with fresh, homegrown lemons! However, these trees are sun-seekers that crave warmth—conditions that most of us in the U.S. don’t have year-round.
Winter Hardiness
Lemon trees live for sunny days and heat. For most of the country, our winters are just way too chilly for them. If you look at the hardiness scales, *Citrus x limon* falls into USDA Zone 9b. This means these citrus beauties can only handle temperatures down to about 25°F (-3.8°C) for very short bursts. Since many regions in the U.S. experience much colder winters, lemon trees generally won’t survive outdoors year-round unless you live in a tropical climate. That’s why, for most of us, growing them in containers is the way to go.
Lemon Trees in Pots
Plants in containers are a bit more vulnerable than those planted directly in the ground. Cold and frost can easily penetrate the walls of the pot, causing the soil to freeze and damaging those sensitive roots. You’ll also see frost damage on the leaves and branches, which can lead to dieback.
Because of this, hardiness zones are really just a rough guide for potted plants. For a potted lemon tree, you really don’t want the temperature to hit the freezing mark (32°F). In fact, even when it’s just slightly above freezing, it’s already getting a bit too uncomfortable for your little tree.
The Outdoor Season: When to Move In and Out
Since *Citrus x limon* is such a sensitive soul when it comes to the cold, you should only move your tree outside once:
- The threat of late spring frost has completely passed.
- Daytime temperatures have consistently settled around 50°F (10°C).
The outdoor season on your patio or balcony officially ends when temperatures start dipping below 50°F consistently. Since a sudden overnight frost can really do a number on your tree, it’s always better to play it safe and bring it inside sooner rather than later.
Overwintering
When it comes to overwintering your lemon tree, you have two main options: “cold” or “warm.” Regardless of which you choose, give your tree as much light as possible and keep it away from chilly drafts.
- Cold Overwintering: Keep the tree in a bright spot between 41°F and 54°F (5°C to 12°C), like a sunroom or a cool hallway.
- Warm Overwintering: You can keep your citrus plant in a heated room, provided it gets plenty of light (you might even need a grow light!).
