Growing citrus fruit in the Midwest is not as difficult as you might think. Having your own supply of fresh, organic fruit is well worth the effort.  

Rachel and I have been successfully growing Key limes in our garden for five years. Each spring, we set them outside for the bees to pollinate. We bring them back indoors in the fall, and the fruit is ready to harvest by winter. 

Key limes are smaller, more acidic and have a stronger aroma and flavor than common limes. They’re also known as Mexican limes or bartender’s limes. Their distinctive taste is why they make the best pies and margaritas.

Key lime trees grown in containers can grow up to 15 feet tall. A smaller pot will keep your tree small. A deep pot will keep your tree from toppling over when it becomes top-heavy with fruit. Placing your pot on caster wheels makes it easier to move as you follow the sun. Your Key lime tree is going to need eight to 12 hours of sun if it’s going to set fruit. When brought indoors, place it near a south-facing window. 

Soil is the next consideration. Never use dirt from the garden. You don’t want to bring insects or disease into your house each winter. There are many good commercial mixes available and your tree will be more likely to thrive. We add composted manure to our mix. You’ll want to re-pot your tree every two or three years to keep it from becoming root bound. You can gently tease the roots loose and place in a slightly bigger pot. There must be enough drainage holes in your pot to allow water to flow freely. When your tree is outdoors, water often enough to keep the soil moist. During the winter, allow the soil to dry between watering. If the leaves start to curl or drop off, your tree needs more water. Spritz the leaves occasionally to maintain humidity. Most homes are excessively dry during the winter. 

During spring, fall and summer, we fertilize twice a month with fish emulsion. We make one last application before we bring our trees in for the winter. The smell of fish emulsion is too strong to use indoors and our trees make it through the winter just fine. There are commercial fertilizers specifically blended for citrus trees. Some are designed for slow release so you don’t have to apply them as often. Just use as directed. 

Key lime trees do best when the temperatures are between 55-85 degrees, though 65 degrees is considered ideal. Remember, temperatures colder than 50 degrees will kill your tree. Bring it indoors by the end of September. I set one of our lime trees out too early last spring and lost a beautiful tree to an unexpected frost.

Key lime trees are evergreens. If you’re lucky, you can have beautiful, fragrant blooms all winter. The small, white, star-shaped flowers can fill a room with citrusy perfume. Once they set fruit, the limes take about four months to ripen. When they turn from dark green to lighter green, they’re ready to pick. Don’t pick them too soon because they only ripen on the tree. If they turn yellow, you’ve left them on the tree too long. 

Consider growing your own Key limes. Bring a little bit of Key West to your Midwest garden.

Rachel and Ivan Minnis are avid gardeners. They live in Leavenworth. For more information, visit The Minnis Rose Garden on Facebook. Contact them at rnlyes@hotmail.com