How to Grow a Dwarf Lemon Tree Indoors
Lemon trees can be grown easily indoors in pots and containers.
Depending on the available area, common lemon trees can be trimmed to the desired size, or one can grow smaller, more compact, or even dwarf varieties, which can be the size of a bonsai tree and fit even windowsill.
Updated: February 10, 2023.
Growing Lemon Trees Indoors
Growing lemon trees indoors in containers protect lemon trees from winter cold and strong winds and enables a grower to enjoy these decorative plants year-long.
Almost any variety of lemon trees can be grown in large enough pots, and when placed on a cart with wheels, it can be taken indoors during cold days and taken outdoors when the danger of frost is gone.
However, growing smaller, more compact varieties allow the gardener to grow them indoors as very decorative plants that bear very tasty and fragrant fruits.
Some of the most popular indoor varieties are Dwarf Ponderosa, Dwarf Improved Meyer, Dwarf Variegated Pink Lemonade, and similar.
Soil Mix For Lemon Trees
The soil mix for an indoor lemon tree should be a mix of good potting soil and organic matter like organic compost and some worm castings. One can add some sand to improve the drainage, which is very important since lemons do require moisture, but they don't like "wet feet"!
Also, the soil must be well aerated and feature a pH of around 6.0 and 6.5.
Before transplanting the lemon tree, check if the tree is growing on its own roots or if it is grafted.
Dwarf varieties are commonly grafted on dwarfing rootstock, with graft union some 2-8 inches (5-20 cm) above the soil top - depending on the used plants and desired plant size.
The amount of soil varies depending on the planned tree size and ranges from just a few liters to a few gallons. Larger containers, which are suitable for growing "common" lemon trees, are much larger.
For example, 24 inches (60 cm) in diameter and 20 inches tall containers have a volume of ~140 liters (37 gallons) when filled with the soil and should be positioned on the cart with wheels for easier transportation.
Since lemons don't like warm roots, go for brightly colored pots, especially if the pots will be exposed to the sunlight as well.
As the lemon tree grows, it is recommended to transplant it into a larger pot every 2-3 years until it grows into a pot of desired size.
When repotting the lemon tree, use a pot that is at least 2 inches (5 cm) larger than the previous one - take the lemon tree outside the old pot, remove the loose soil from the root ball, trim down a root ball (but not by much) and replant it into a new pot at the same plant height.
The best period for repotting is late winter and early spring when the plant is starting with vigorous growth, allowing the roots to spread in the pot quickly, enjoying all the benefits of the larger pot and new soil mix.
Obtaining Dwarf Lemon Trees
Although lemons can be grown from seeds, the best course of action is to check local or online garden centers and purchase a small certified lemon tree.
However, if You want to obtain a very specific lemon tree (from friends, neighbors, etc.), feel free to try grafting it or preferably rooting a small lemon tree branch using a rooting hormone:
- In a small 4-6 inches pot, mix some good potting soil,
- Take 1-2 branches from the lemon tree with just 3-4 leaves,
- Cut the leaves to half or 2/3rds (not absolutely required, but...),
- Put the branches into a rooting hormone,
- Plant the branches into the pot and water them thoroughly for the next 2-3 weeks.
When the branches show signs of new growth, water them less often. Since this method works very well, most growers place just one branch per pot, so there is no need to remove one of the branches.
The best period for rooting a branch is in spring or early summer when lemon trees grow the most.
Watering the Lemon Trees Grown Indoors
Watering lemon trees in containers must be done regularly, especially during summer months, when plants growing outside must be watered on an almost daily basis.
If the lemon trees are kept inside year long, water according to room temperature. Since waterlogged soil must be avoided, don't use too much water - if there is excess water in the container tray, decrease the amount of water.
To keep the lemon tree happy, feel free to check the soil condition by driving the finger into the soil 1-2 inches - if the soil feels moist, don't water it. If the soil feels dry, water it until the water starts to exit through the drainage holes.
On average, lemon trees grown indoors should be watered once a week during summer and every 2-3 weeks during the winter.
How To Fertilize Lemon Trees
Fertilization is very important since lemon trees indoors are grown for their fragrant fruits but also for decorative purposes.
If you have just a few dwarf lemon trees, the simplest solution is to use liquid fertilizers for citrus fruits enriched with various microelements - just add the required amount of fertilizer when watering the plants, and your plants will be happy. Of course, this is not the cheapest solution.
Another solution is using fertilizer spikes - drive one or more spikes into the soil every few months, and they will provide all the required nutrients that lemon trees need.
NPK fertilizers with a slow, gradual release are another option - add the required amount of fertilizer to the soil and carefully work the fertilizer into the soil.
Organic fertilizers like organic compost and worm castings are excellent for improving soil quality and slightly acidic pH. But, organic fertilizers can also cause some unpleasant smells to develop, so be careful - when adding organic fertilizers to indoor plants, always cover them with some topsoil, just to be sure.
When lemon trees are kept outside, one doesn't have to worry about pollination - bees and other insects are attracted to lemon flowers and will do their job well.
However, when lemon trees are kept indoors, one must pollinate the flowers manually.
The best and easiest way to do it is to take a small, soft paintbrush and transfer pollen from flower to flower. It takes just a few seconds for each flower and achieves very good results.
Using "high-tech" air pumps and similar tools maybe (just maybe!) produces better results, but why bother ... IMHO, of course!
Lemons prefer full sun positions, so grow them near large windows facing south (or north if you live in the southern hemisphere).
To improve the health of the plants, artificial lightning can be used to increase the light intensity and daily light period - aim for at least 10, but not more than 18 hours of light.
Note: lemons will grow happily next to the large window with 7-8 hours of daylight but will grow slower than with 10-16 hours of sunlight. To promote uniform growth, rotate the plant's side facing the window every few days.
Lemons prefer warmer areas but will grow at room temperature well. When positioning your lemon tree, place it away from cold or hot drafts.
The acceptable temperature range is between 70 and 90°F (21 to 32°C), with the best temperature around 85°F (29-30°C) - this also depends on the chosen variety.
Above 105°F (40°C) lemon tree will stop growing, while below 50°F (10°C) lemon tree will go into dormancy. Temperatures below 30°F (-1°C) can cause plants to drop their leaves, while prolonged exposure to such low temperatures will damage the fruits and the tree, killing it in the end.
Long story short: - lemon trees are easily grown in containers, inside and outside. Dwarf lemon trees can be very decorative plants bearing full-size lemon fruits.
If you like lemons, give them a try, and they will reward You with abundant flowers and numerous great-tasting lemons.