With their glossy green foliage, their masses of beautiful, fragrant flowers, and enormous productivity of tart and tasty fruit, lemon trees are a great choice for nearly every home gardener.
Even if you don’t grow any other fruit and vegetable plants, it’s good to get to know how to grow a lemon tree. With simple lemon tree care, your lemon tree can become the basis for a kitchen garden you will use every day.
Winter cold is the limiting factor in choosing to grow your lemon tree in-ground or in a container, so you can take it indoors for protection from the cold. If you live anywhere north of Florida, Central Texas, Southern California, or the immediate Gulf Coast of the United States, your best bet for success is growing your lemon tree in a container.
Meyer Lemon trees sometimes survive temperatures as low as 10° F (-12 C), but most other varieties are killed by hard freezes. Some can’t withstand even a light frost.
How To Grow A Lemon Tree Indoors
We will have a comment on how to grow a lemon tree in the ground outdoors a little later in this article. But since most of you will be keeping your lemon tree indoors at least part of the year, we will begin with everything you need to know to grow your lemon tree indoors.
Most of the information on how to grow a lemon tree indoors is similar for growing outdoors, so you can use this information for both locations.
Start by making sure you have a good potting soil
Good potting soil is crucial to long-term success with your lemon tree. Bagged soil or compost will be fine for a short time, but after a few months your lemon tree will stop growing vigorously.
Lemon trees have finicky roots. They grow naturally in arid climates with well-draining, sandy soils. The soil you choose for your container-grown citrus has to duplicate the soil lemon trees have in that environment. The roots of your lemon tree will rot and die if you go with anything other than a light, well-drained potting mix that you will probably have to make for yourself.
The potting soil that works best for container-grown lemon trees is equal parts of:
- Sphagnum moss
- Coconut fiber
What you are looking for is a potting mix with a gritty texture, so that water can drain away from the roots while the potting mixture stays moist. Perlite and vermiculite are worth looking for. They hold on to water like a damp sponge.
If you can’t locate these ingredients, you can use two parts sand to one part bagged compost. This mixture drains water well but it doesn’t hold damp moisture the way mixtures with perlite and vermiculite do.
Use A Citrus-Specific Fertilizer on a Citrus-Specific Schedule
Lemon trees need more phosphate than other plants commonly grown in containers. They need plant food made for citrus and avocados, or you can give them a few tablespoons of bone meal for each gallon of potting soil (30 grams of bone meal for every 5-liter container) twice a year. If you are vegan, you can use a regular plant fertilizer plus crushed rock phosphate.
Citrus need to be fertilized twice a year. It’s very important to fertilize them at the right times. Fertilize once in the spring and once in the summer, but avoid fertilizing your lemon tree in the fall and winter.
Reducing the fertility of your potting mix slows the growth of the plant, so there is less tender vegetation that can be damaged by cold. It also slows blooming so the plant isn’t as sensitive to reduced light and warmth.
Make Sure Your Potting Mix Has an Acidic pH
Lemon trees prefer soil that has a pH of 5.5 to 6.0. That’s not as acidic as you would need to grow, for instance, blueberries, but it’s more acidic than most naturally occurring soils in Texas and Southern California. Keeping the potting soil at the right pH is one of the reasons not to just scoop up some dirt from the yard.
Using a commercial fertilizer blend designed for container-grown citrus will keep your tree’s potting soil at the right pH. You can acidify potting soil by adding aluminum sulfate or sulfur, but they smell bad, and it’s easy to use too much. If you add chemicals to the soil to lower pH, be sure to test pH with a meter or test strips before you add any chemicals to make sure they are needed, and a few days after you add any chemicals to see whether you need to add more or it’s OK to stop.
Keep Your Lemon Tree Out of the Cold
Lemon trees are stunned by temperatures below 45° F (about 7° C). They become more susceptible to disease when they are exposed to temperatures between 45° F (7° C) and freezing. For the first two years after planting, most lemon trees can be killed by even a few hours below freezing. Mature trees of all varieties usually can stand a hard freeze, but even Meyer lemons need protection for temperatures below 20° F (-7° C).
Sometimes your lemon tree will get caught in a hard freeze and the top will die, but later it comes back from the root. This is not a “lemon” tree you want to keep. Lemon trees for container production in USDA Hardiness Zones 8 and lower are usually grafted onto trifoliate orange rootstock. This rootstock is chosen because it resists cold damage. However, if the lemon grafted onto the trifoliate orange dies, what you will have left is a plant that produces rock-hard, bitter fruit.
Be Careful About Leaving Your Lemon Tree in the Heat, Too
Lemon trees shouldn’t be placed directly next to forced-air heaters, fireplaces, or stoves indoors. When you are moving your lemon tree outside for the summer, give it a gentle transition. Put it out in morning sun and bring it back indoors at noon for the first two or three days. Then leave it out full-time.
Bring your lemon tree back indoors when outside temperatures go above 105° F (41° C) or below 45° F (7° C) at night.
Your lemon tree will tell you that it’s not ready to go outdoors or indoors by dropping its leaves. Temperature shocks will cause lemon tree leaves to turn yellow and fall off. Avoid sudden swings in temperature to keep your lemon tree healthy.
Make Sure Your Lemon Tree Is In a Sunny Location
Lemon trees only need three hours of sunlight a day to have healthy, attractive, green foliage. For blooming and fruit production, however, they need a minimum of four to six hours of full, direct sunlight every day. Eight to twelve hours of full sunlight is better. Extra sunlight powers fruit production.
When you take your lemon tree indoors for the winter, it needs at least three hours of direct sunlight in a sunny window every day to maintain its foliage. Supplementing natural sunlight with a grow lamp will keep your lemon tree healthier.
Beware of keeping lemon trees in glass greenhouses in the summer, to avoid overheating.
Don’t overwater your lemon tree!
The #1 way home gardeners kill their container-grown lemon trees is watering them too much. There are a couple of easy ways to make sure you are giving your lemon tree the right amount of water.
One way is to buy a moisture meter. They are available for $10 to $15 from nurseries and garden supply centers. It will tell you whether the soil in which your lemon tree is growing is too wet, too dry, or just right.
The other way to test for moisture is the finger-poke method. Stick your finger into the soil up to your knuckle. If the soil is dry, then water. This method only works, however, if you have a well-draining potting mix and a pot with holes in the bottom.
You can be sure you are overwatering if water collects on the surface of the soil. This can happen if you don’t have drainage holes in the bottom of your lemon tree’s container.
Soggy soil can result in a bacterial infection of your lemon tree’s roots called root rot. It’s not hard to recognize root rot.
- You smell a sour odor coming from your potting soil.
- Your lemon tree’s leaves turn yellow and fall off.
- Your lemon tree dies from the top down.
You may be able to save your lemon tree if you recognize root rot early and stop watering!
Don’t Try to Grow a Lemon Tree from Seed
Just about any gardener can grow a lemon tree from seed, but no gardener should.
Plants don’t grow true from seed. They will not have the same characteristics as their parent plants. And you have to take care of a lemon tree grown from seed for two or three years longer than a container-grown plant before you get your first lemons.
When you plant a lemon seed, you don’t know who its father was. The plant that produced the lemon that made the seed may be a beautiful tree that produces great fruit, but the pollen that created the seed could have come from a defective tree. It can take as long as 10 years to get fruit from a lemon tree you grow from seed, and you could wait all that time only to learn you have a plant that produces inferior fruit of defective quality
The lemon trees you buy at the nursery are cloned from known disease-resistant, highly productive plants. They are grafted onto rootstock of another kind of citrus to make them cold-hardy and drought-resistant. It’s just not possible to get the results from a lemon tree grown from seed that you can get with a lemon tree grafted onto a rootstock.
Buying a grafted tree from a nursery also ensures that you will get a dwarf tree. Most of us don’t want houseplants that grow 20 feet (6 meters) tall! The nursery will sell you a lemon tree of known genetics that you could use to perform as described.
And because grafts are taken from lemon trees that are already producing, you won’t have to wait for your tree to “grow up.” You’re getting a clone of a tree that already produces lemons. You’ll be getting fruit in just a year or two.
Transplant Your Lemon Tree Within a Week or Two of Buying It
Lemon trees from your nursery come in tall, narrow pots called root pots. These pots don’t give your lemon tree’s roots any space for additional growth. If you keep your lemon tree in its root pot too long, it can become stressed.
When you transplant your lemon tree from its root pot to its container for your garden, however, you shouldn’t put it in too large a pot. People get the idea that they only want to transplant their lemon tree once, so they will put it into the largest pot possible.
This is a bad idea because the size of the pot makes a big difference in how dry the soil gets. If there is a lot of soil in the pot, but the lemon tree doesn’t have an extensive root system yet, the soil will hold on to too much water. This can cause root rot that kills your lemon tree.
Instead of a large, plastic pot, which keeps water in the soil, use a smaller, clay pot, which absorbs excess water from the soil. This helps keep roots aerated and healthy.
When you are ready to transplant your lemon tree, put a couple of handfuls of soil mix into the bottom of the pot, to keep your tree upright. To get the lemon tree out of its root pot without damaging any roots, put your thumb on one side of the stem of the plant and your index finger on the other side of the plant. Turn the pot upside down. Squeeze the bottom of the pot with your other hand, give it a couple of taps, and let gravity do the work of removing your lemon tree from its pot. Never pull a tree out of its root pot.
Make sure the trunk of your new lemon tree has not been buried in soil. This often happens in transit. Brush any soil away from the trunk of the plant. Backfill the space around the roots with more potting mix up to the level of the trunk.
Now it’s time for your lemon tree’s first feeding. Take about a cup (200 grams) of fertilizer around your plant, and work it in with your fingers. For future fertilizing, you can top dress with the fertilizer, scattering in on the surface of the soil without working it in. It takes time for fertilizer to reach the roots, so this way you are giving the newly transplanted tree quick nutrition. In the future, your tree won’t need the additional nutrients as quickly.
Make sure the top of the soil in the container is just a little below the bottom of the trunk. This gives the soil a tiny slope down and keeps the trunk from becoming waterlogged. It’s also important to remove any tags or plastic ties that may be attached to your plant. If you leave them on your lemon tree, they will girdle the trunk and kill the tree.
The first time you plant a lemon tree, give it a good soaking. If you have the right soil type, the water will run right out the bottom of the container or into the subsoil.
Pruning Your Lemon Tree
Pruning your lemon tree is an important step to having a healthy and productive citrus tree. Check out our entire post on Pruning Lemon Trees for more information.
Lemon Tree Diseases
Lemon tree diseases is another big topic that we have covered in more detail. Check out our post on Lemon Tree Diseases to learn about the most common diseases, how to prevent them, and how to treat them.
Lemon Tree Bugs and Insects
There are a number of lemon tree insects that you will need to keep an eye out for while growing your lemon tree. Read all about lemon tree pests and how to prevent them.
How To Grow a Lemon Tree Outdoors
The rules for how to grow a lemon tree outdoors is pretty much the same as the rules for growing lemon trees indoors. Just provide trees the same conditions outdoors that you can give them indoors! But unless you live in USDA Hardiness Zone 9, 10, or 11, it’s a lot easier grow beautiful and productive lemon trees in attractive pots.
We have posted other articles on lemon tree diseases and pruning your lemon trees. There’s just one more thing you need to know about growing lemon trees either indoors or outdoors:
One lemon tree is good, but two lemon trees are better! See Nature Hills Nursery for their current selection of citrus!