Indoor Lemon Tree Care: How to Grow an Indoor Lemon Tree

An indoor lemon tree is a dwarf citrus tree that grows smaller than outdoor varieties but still bears full-sized lemon fruit. Mature outdoor lemon trees typically grow to about twenty feet tall in their natural environments. Dwarf varieties that grow indoors reach only four to ten feet in height and bear fruit more quickly than their larger outdoor counterparts.

These indoor plants require the mild winters and warm temperatures found in USDA Hardiness Zones 8–11 to thrive outside, but home gardeners who live in cooler climates can grow them successfully inside of their homes.

Indoor lemon trees grown from seed will likely take many years to bear fruit. Your best bet is to transfer a two- to three-year-old dwarf tree purchased from your local nursery or garden center into an indoor pot. Follow these steps to grow a lemon tree indoors.

1. 1. Choose the right tree. The best types of dwarf lemon trees for container growing are Ponderosa and Meyer lemon trees. The Ponderosa is a hybrid citron-lemon tree that yields the largest lemons. The easy-to-grow Meyer lemon tree is a hybrid of a Mandarin orange and lemon tree. If you want to grow the latter variety, try an ‘Improved Meyer’ cultivar, which is resistant to common citrus tree viruses. Variegated pink lemon trees are also indoor-friendly and bear lemons with pink flesh.
2. 2. Choose an appropriate pot. Plant your indoor lemon tree in a terracotta pot with drainage holes to prevent your tree from becoming waterlogged and developing root rot. To determine your pot’s size, measure your tree’s root ball and look for a pot that’s at least two inches larger on all sides. As your tree grows, transplant it into a larger pot if it becomes root-bound.
3. 3. Use a well-drained potting mix. Look for a potting mix formulated specifically for citrus trees. The ideal potting mix should dry out easily to prevent soggy soil. Fill your container with the potting mix, and dig a hole for your tree.
4. 4. Plant the tree. Determine the proper depth to plant your tree’s root ball by locating its root flare (the wide bottom part of the trunk), which should be directly above the soil line. Leave an inch or two of room between the soil line and the top of the pot so that the soil doesn’t spill out during watering.
5. 5. Water thoroughly and treat with a starter formula. Water your lemon tree until water begins to seep out the drainage holes. The next day, treat the soil with a plant starter formula to reduce transplant shock.
6. 6. Choose the tree location. Citrus plants require eight to ten hours of direct sunlight a day to bear fruit, so place your tree near a south-facing window. If you can’t find a spot in your home with enough hours of full sun per day, use an artificial grow light. Indoor lemon trees prefer temperatures between sixty-five and eighty degrees Fahrenheit, so avoid placing them near any heat or air conditioning vents.

Follow these indoor lemon tree care tips to give your tree the greatest chance of a bountiful lemon harvest.

• Feed with special fertilizer. Fertilize your tree with a high-nitrogen organic fertilizer to give it the nutrients needed to prosper. Follow the instructions on the fertilizer package to determine how much to use and how frequently to apply.
• Maintain pest control. Monitor your lemon tree for common houseplant pests like spider mites and aphids. At the first sign of an infestation, immediately treat your tree with an appropriate pesticide.
• Pollinate the tree’s blossoms. You’ll need to self-pollinate your indoor lemon tree to ensure fruiting. To do this, take a small paintbrush or cotton swab and swirl it around the center of a blossom to collect some pollen. Repeat that step with every bloom on the tree once a day with the same pollination device until fruit starts to form.
• Prune the tree. To ensure your tree doesn’t outgrow a small space, prune its root system every three to four years. To root prune a tree, carefully remove the tree from its pot, delicately trim the root ends with a pair of pruners, and place it back in its hole.
• Water sparingly. Only water your lemon tree when the top two inches of the soil are dry. Keep the soil moist without oversaturating it. Stop watering once the liquid seeps out of the pot’s drainage holes. Water your lemon tree more frequently during the summer than you do in the winter months, especially if you move it outside in the summer.

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