Ask a Master Gardener: How to grow Meyer lemons indoors
“It may be better to simply consider your citrus a nice houseplant that might produce fruit as a bonus," University of Minnesota Extension suggests.
Q: I bought a lemon tree at one of the big-box stores at the mall last year. It’s doing well. It had some bugs on it that I wiped off and they don’t seem to have come back. It put out some flowers but they didn’t turn into lemons. How can I get it to bear fruit?
A: It can be tough to get a tropical tree to bear fruit indoors in Minnesota. We don’t have quite the right temperature, humidity and light conditions.
Extension suggests: “It may be better to simply consider your citrus a nice houseplant that might produce fruit as a bonus.”
One problem is that there aren’t pollinators in your home to move the pollen from flower to flower. So you will have to do that yourself if you want the tree to bear fruit. You can move pollen with a cotton swab or shake the flowers so that the pollen falls from one flower to another.
You did the right thing removing the insects from your tree. Lemons grown indoors can attract several pests, and the first line of defense is to keep the leaves clean by periodically washing them with water.
Healthy plants are also better able to defend themselves against insects, so you want to be sure to keep your lemon tree properly watered and give it enough light. It will prefer a location with at least six hours of sunlight. It should be kept moist but not waterlogged.
The best way to water it — and other houseplants, too, for that matter — is to water until water runs out the hole in the bottom of the pot, and then pour off any standing water from the saucer underneath. We find that people tend to kill plants by overwatering more than underwatering. Poke a finger into the soil and feel a couple inches down; if it’s dry, it’s time to water. If not, hold off.
You can move your tree outside in the summer, but make sure to acclimate it slowly to outdoor conditions. Start it off in a shady spot for an hour or two, then gradually increase the amount of time it’s outdoors and the sun it receives. When it comes time to bring it back in, check it carefully for insects.
Fertilize with a fertilizer meant for acid-loving plants. As with all houseplants, fertilize when the plant is growing, not in winter, when plants tend to be more dormant.
There’s more information about growing lemons and other citrus indoors at extension.umn.edu/houseplants/growing-citrus-indoors.
Written by U of M Extension Master Gardeners in St. Louis County. Send questions to firstname.lastname@example.org.