Lemon trees cannot tolerate temperatures lower than 27℉ (-2.7℃). Moreover, the younger lemon trees are less likely to survive winter well without some help.
If you have a dwarf or young potted lemon tree, bringing it indoors is the best way to help it survive. If left outdoors, an established lemon tree can survive mild winters when protected with a shield.
How Cold Hardy Are Lemon Trees?
Lemon trees are quite cold-hardy and may surprise you by being more tolerant of cold than other plants in the garden!
Lemon trees can survive in temperatures around 27/28℉ or -2.7/-2.2/℃. Anything lower than this will result in loss of leaves.
Although lemon trees survive in these temperatures, flowers and fruits may get damaged at colder temperatures.
Many areas in the USA can be colder than this temperature. This is the reason why everyone can’t plant a lemon tree in their garden. The lemon trees wouldn’t be able to survive in such a climate.
An alternative to keeping lemon trees outdoors in the cold in winter is to bring them indoors. However, you would have to sacrifice your standard size lemon tree and pick a dwarf lemon tree instead.
These are our 5 best dwarf lemon trees for growing indoors.
Which Tolerates Cold Better- Indoor Lemon Tree or Outdoor Lemon Tree?
During winter temperatures indoors are much higher than the ones outdoors. But, the biggest factor is that indoor plants are protected against frost and wind. Two conditions that would otherwise damage your lemon trees.
Thus, an indoor lemon tree stands a greater chance of surviving than an outdoor lemon tree. And it’s not just protection from cold elements that support this fact.
While indoors, there are so many conditions that can be controlled which when outdoors are uncontrollable.
You can directly control temperature, watering, and even sunlight (using a LED grow light) provided to an indoor lemon tree.
Outdoor lemon trees can only be protected from the cold so much. Beyond this, they are extremely vulnerable to the elements when left outside.
The only way to protect an outdoor lemon tree is to cover it up and build a shield around it. Additionally, you can opt to buy a lemon tree with a cold-hardy rootstock.
Evidently, an indoor lemon tree would fare better than an outdoor lemon tree. This is particularly true in areas where cold winter weather is more prominent than sunny summer.
Tips to care for Lemon tree brought indoors during Winter
If you have a potted outdoor lemon tree, bringing them indoors will be the best way for them to overwinter. A lemon tree has better chances of surviving indoors where you can watch over and help it better.
- Get them acclimatized by bringing in the shade before for a few weeks before you move them indoors.
- Thoroughly check for any signs of aphids and other insects. Wash them with water/ insecticidal soap or spray Neem oil. Let it completely dry before bringing the tree inside.
- Choose the south-facing window so that they receive maximum light.
- The Lemon tree should not be kept near the heating vents.
- Lemon trees thrive well in some humidity. You can help them by placing the shallow container of pebbles under the container and watering it to half the height of pebbles. Water must not reach the pot.
- Watering should only be done when required during winter. You can check it by touching the soil.
- Do not apply fertilizer during the winter months as new growth prompted by it may not do well under colder conditions.
How to Care For an Indoor Lemon Tree During Winter?
Do you live in one of the colder states in the USA? If so, growing a lemon tree in a pot indoors is your greatest chance of success.
To pull this off, you’ll have to know what your lemon tree needs when indoors to keep it alive and well. More about this is below.
During winter, plants generally need little to no watering. While outdoors, lemon trees do not have the comfort of having water limited to them. Rainfall could easily be too much for them to handle.
Water lemon trees only once a month during the winter seasons. Because the lemon tree is indoors, you can even test the soil and choose when that watering needs to happen.
Not sure about how much water your lemon tree will need? You may want to read about how much water lemon trees need.
Sunlight / Grow Light
The optimal amount of sunlight will not be available indoors during the winter months. This poses a problem since sunlight is crucial for keeping a lemon tree alive. But, growing any plant indoors comes with an advantage.
Artificial light helps to improve the temperature as a whole. The LED grow lights help to provide light wavelengths that plants can use for photosynthesis.
This can act as a substitute for sunlight and helps to keep your indoor lemon tree alive. Although you may not be able to give your lemon tree the full 8+ hours of sunlight it needs, it can get enough to stay viable over winter.
Being outdoors leaves your lemon tree vulnerable to diseases that are induced due to colder spells of weather.
Indoor environments can be both humid and warm. These conditions are capable of harboring infections. Particularly fungal infections since spores are already present in the soil already.
Regularly inspect your lemon tree to make sure it isn’t being infected.
You can take a step further to prevent this by wiping the leaves with a ball of cotton wool. This may also help to unclog leaf pores and maintain transpiration.
Lemon trees like other citrus trees need quite a bit of humidity to prevent ill effects from showing through the foliage. If your lemon tree is blooming or about to, a lack of humidity will affect flowering and fruit formation.
Using an artificial humidifier, you can make sure the air isn’t too dry. Air that’s too dry may also cause faster drying out of the soil. This will mean a closer eye has to be kept on watering efforts and soil moisture. A humidifier definitely helps in all aspects.
Withhold Fertilizer During Winter
While your lemon tree is trying to survive winter, you should never offer it any form of fertilizer, organic or artificial!
This abundance of nutrients would promote growth. New growth is very vulnerable to the cold and is likely to not survive. This further compromises the lemon tree.
Do Potted Lemon Trees Lose Leaves in Winter?
Sometimes despite offering them almost everything they need, they will still tend to lose a few leaves. Because let’s face it, indoor conditions cannot be perfectly made to mimic outdoor conditions! The loss of a few lemon leaves is understandable.
If your lemon tree is losing many leaves, it could be Winter Leaf Drop (WLD). This condition occurs when the respective parts of the lemon trees are at very different temperatures.
The leaves usually warm up and get much hotter than the roots. If the roots don’t manage to warm up as well, they may not be able to help regulate the temperature of the leaves.
As a result, the stressful situation causes leaf discoloration. If it persists your lemon tree can expect to lose a lot of leaves, almost leaving it bare if summer doesn’t arrive in time.
Winter leaf drop is common among lemon trees that you house indoors during winter.
Do Potted Lemon Trees Change Leaf Color in Winter?
During winter, you may decide to bring your lemon tree indoors. However, there are obvious changes that will never be the same no matter how hard you try.
A variety of conditions could cause lemon tree leaves to change color. Here are a few scenarios:
- Nutrient deficiencies
- Lack or excess of water
- Temperature shifts
- Soil issues
- Disease or pest infestations
Your green foliage will only be so if you discover the discrepancy and fix it at the earliest.
The coldest temperature lemon trees can withstand are 27/28℉ or -2.7/-2.2℃. However, from 22℉ the lemon tree will start to be in danger of dying off!
But, to help your lemon tree overwinter you can bring it indoors if it is a dwarf or potted lemon tree. With care and monitoring, you can control water, humidity, sunlight, and temperature within your house where the lemon tree is growing.
When temperatures heat up outside, you can move your lemon tree outdoors. But, make sure you care for them well during the winter season.
Put your mind to rest; Are lemons trees or bushes?
Yes, if your lemon tree is staying outdoors for winter, you should definitely cover it up for protection. You can choose to use burlap but any other breathable fabric will do. Use 3 or 4 sticks to hold the fabric in place.
Preferably you should take your lemon tree indoors a bit before winter. This is only to help it adjust to indoor conditions better.
Bringing them inside suddenly may repel them into a state of shock which will come with undesirable appearance changes as well as alliteration to normal functioning.