Lemon trees are a popular choice for home gardens and containers in warm climates. But what about growing lemons where winters are cold? With proper care and protection, lemon trees can survive and even thrive through winter outdoors in many cooler regions. In this comprehensive guide, we’ll explore everything you need to know about overwintering lemon trees outside, including cold hardiness, protection methods, best varieties, and tips for success.
How Cold Hardy Are Lemon Trees?
Lemon trees are considered moderately cold hardy meaning they can tolerate brief temperatures down to around 25°F when mature. However young trees and prolonged freezing weather is damaging. Their cold tolerance depends on several factors
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Type of lemon Some varieties are more cold tolerant like Meyer and Lisbon. Eureka and variegated types are less hardy.
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Age: Mature, established trees handle cold better than young saplings. Those over 3-4 years old do best.
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Health: Vigorous, healthy trees are more resilient to cold damage. Prior issues make them prone to problems.
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Climate: Areas with milder winters allow for easier wintering than those with harsh, extended freezes.
So while lemons can briefly survive temps in the mid-upper 20s°F, protection is needed when mercury remains sub-freezing.
Protecting Lemon Trees Over Winter
If you live where winters are cold, taking steps to shield trees from freezing is key:
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Location: Choose a sunny microclimate protected from wind and with good drainage. South-facing spots near foundations hold heat.
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Insulate: Mulch 6-12 inches deep insulates soil and roots. Wrap trunks with burlap.
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Covers: Blanket trees with fabric row cover, plastic sheeting, tarps or blankets during hard freezes. Avoid contact with foliage. Ventilate on warm days.
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Heating: String outdoor-safe holiday lights or heating cables under covers when extremely cold. Use low wattage bulbs to prevent burns.
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Windbreaks: Build temporary wooden enclosures to shelter from winter winds.
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Watering: Water minimally only when very dry. Avoid fertilizing.
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Pruning: Prune lightly to avoid new growth. Do major pruning after last frost.
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Monitoring: Check for damage like curled leaves. Adjust protection as needed.
Growing Lemon Trees in Pots
Container growing allows lemon trees to be moved into protected areas during winter. Use a 20+ inch diameter pot and free-draining potting mix amended with compost. Maintain even moisture and fertilize in summer. Before winter, prune for size and ease of moving. Monitor soil moisture in storage and provide ample light. Bring back outside after all chance of frost.
Best Lemon Varieties for Cold Climates
Some lemon types perform better where winters are cold:
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Meyer – Very cold hardy, surviving down to 20°F. Sweeter flavor.
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Lisbon – Traditional lemon hardy to the mid 20s°F when mature. Good producer.
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Variegated Eureka – Gorgeous variegated foliage. Tolerates temps to the upper 20s°F.
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Yuzu – Unique citrus hybrid very cold tolerant, handling 5°F. Tart taste.
When buying trees, select those grafted onto hardy, resilient rootstock for improved winter survival.
Is Overwintering Lemons Outside Worthwhile?
Growing lemons where winters are cold takes diligence and proper winter care. For gardeners willing to put in the effort required, homegrown lemons are an amazing treat. Enjoying sun-ripened lemons straight from your tree makes the winter protection worthwhile, even in cooler climates.
With the right preparation, varieties, age, and location, lemon trees can make it through cold seasons in many areas. While not foolproof, proven overwintering methods help lemons survive and thrive outside through winter. A little extra attention goes a long way when growing these special fruit trees beyond the tropics.
In Summary
While lemon trees prefer tropical conditions, they can develop good cold hardiness when mature. With thoughtful plant choices, proper care, strategic overwintering methods, and a little luck, you can have homegrown lemons, even where winters turn frigid. Lemon trees might require coddling, but the reward of plump, fragrant lemons on your own tree makes the effort worth it.
Lemon Trees are Cold-Hardy
When we moved from our bungalow to a house with an old sunroom that stayed just above freezing over the winter, my lemons were happier than they had ever been. The cool winter temperatures suited them. There were fewer insect pests, and when spring came, those trees flowered as they had never flowered before.
Lemon Fruits Ripen in Moderate Climates
While Bob grows lemon trees outdoors, he grows oranges and other “sweet” citrus in a greenhouse. Lemons don’t need this extra heat to ripen.
Lemons ripen in climates too cool to properly ripen other citrus.
Canadian citrus expert Bob Duncan lumps citrus into two broad groups: “sweet” citrus such as oranges and grapefruit, and “acid” citrus such as lemons and limes.
This distinction is very useful for cold-climate gardeners to understand because sweet citrus need a sustained high summer heat for sugars to develop in the fruit. Acid citrus, on the other hand, doesn’t need sustained heat to ripen.
Bob lives in the Pacific North-West region of North America, which has a moderate climate. To get his sweet citrus to ripen, he uses an unheated greenhouse. The greenhouse is for additional summer heat — not because of winter hardiness!
BUT THE LEMONS — an acid citrus — don’t need the greenhouse to ripen, even though the summer temperatures are not hot where he is. “With lemons, they don’t need as many summer heat units,” Bob explains. (“Heat units” is a concept often used in agriculture. It considers daily maximum and minimum temperatures and the heat that a plant experiences during a growing season.)
When you consider its combination of cold-hardiness and ripening requirements, lemon makes a very practical citrus for the home gardener in a cold climate.
How To Keep Your Citrus Alive In The Winter
FAQ
How cold is too cold for a lemon tree outside?
Lemons and most citrus trees will get frost damage at temperatures under 30 degrees Fahrenheit. If your lemon tree is in a pot, move it to a protected location before any frost hits. It’s a good idea to let it acclimatize a little at a time before any big temperature changes such as going indoors or back out again.
What should I do with my lemon tree in the winter?
Lemon trees are susceptible to freeze damage when temperatures get to about 30 degrees or lower. If the tree is left outside for the winter, it should be placed in an area that receives as much sun as possible, preferably on the south, southeast side of the house to protect from northern/northwest winds.
Will a lemon tree recover from freeze?
While alarming, leaf fall alone does not indicate tree death. If the wood remains healthy, the tree will recover and put out new growth in the spring.
Can my lemon tree that is in a container stay outside over there in winter?
You may also want to know how overwintering your potted citrus trees helps in winter time. The best option is to grow your citrus tree outside in full sun for as long as possible and move them inside during winter. The exact time to move your potted citrus indoors will vary based on your climate.