Despite our dry environment, you can raise tropical plants with the proper care and conditions.
When considering which plants to grow in your Colorado garden, a lemon tree may not be the first that comes to mind. But Troy Cobb, greenhouse manager at Fort Collins Nursery, said citrus and other fruiting tropical plants can actually thrive in our dry conditions.
All it takes is the right care, at the right time.
For instance, these heat-loving plants should be kept inside during Colorado winters, with access to ample sunlight.
“When you’re growing them indoors, you need a south window or a west window,” Cobb said. “They’re going to want as much light as they can get.”
As spring sets in and daytime temperatures warm, itap safe to put the citrus plant outside, as long as you slowly ease it into full sun and bring the plant back inside each night.
“Once the night temperatures in the spring are staying consistently at about 40 (degrees) or more, it can stay outside,” Cobb said.
A citrus plant is happiest when it’s outside in the summer, enjoying the season’s strong light and hot temperatures. A plant thatap been outside all summer will also be better suited to withstand the transition into autumn, making it stronger overall.
“In the late summer and early fall, they’re starting to get used to the big swings in day-to-night temperatures,” Cobb said.
Eventually, when the cold dips below 40 degrees again, it’ll be time to bring the plant back indoors. However, to avoid transferring problems to your other houseplants during this period, quarantine the citrus and watch for pests. Keep an especially watchful eye out for spider mites, which tend to attack citrus in the winter when our indoor plants are dry.
Pot size and soil are additional considerations when growing citrus, because the top of the plant grows about three times as fast as the roots. Planting a tree in a pot thatap too big, or in soil thatap too heavy, can cause slow-growing roots to drown.
“It’s going to be in that (original) pot for probably three to five years before it will need to go to another pot, because the roots just grow that slowly,” Cobb said.
When you eventually move your citrus to a new pot, remember that the sun is a tropical plantap best friend. “Every plant’s going to go through transplant shock, and the more light that the plant has throughout the day, the faster it will bounce back.”
Cobb said every citrus fruit is equally easy to grow in Colorado — except for calamansi (often known as calamondin), a lime that turns orange and is even more user-friendly than lemons. He has also had success growing mangoes, pineapple guavas and olives in Colorado. He has harvested avocados, too, though these trees need to be quite mature before they produce fruit. Passion fruit is another relatively easy plant to maintain, but as an aggressive-growing vine, it requires ample space.
Cacao is at the top of the list of tropical plants that Cobb doesn’t recommend. It simply craves too much humidity. Itap also possible to grow miracle fruit, a plant that gets its name from berries that make sour foods taste sweet, though it’s highly susceptible to mealy bugs, another common pest.
Perhaps the greatest perk to growing citrus is that it can start producing fruit when the plant is still young. Fort Collins Nursery sells citrus in an eight-inch pot — their smallest fruiting size — and yields will only continue to increase with time.
“The bigger the plant gets, the more energy it can support, and the more fruit it can make,” Cobb said.
While a citrus plant is technically self-fertile when outside, bees still play an important role in pollination, which ensures a fruiting plant. If you’re growing a lemon or lime tree indoors, there’s no shame in assuming that responsibility yourself.
“Get a little paintbrush, kind of swirl it around inside the flower, and go from flower to flower to pick up pollen and move it into the next one,” Cobb said. “You’ll get a better yield if you actually act like a bee.”
Michelle Polizzi is a freelance travel, culture and lifestyle writer based in Denver.
