Growing up I had a huge backyard to run around and play in. I would stay outside with my friends until the sun went down and the huge mosquitos would come out. And even then we’d play until my mom would call me inside. There was a lot going on in that backyard, but it easily housed two huge grove-worthy citrus trees. Not every backyard has that kind of space, but luckily that’s ok. If you’re interested in growing citrus trees, but don’t have a lot of space, you can grow them in pots. There’s a lot of citrus fruit you can choose from to grow. Some of my favorites include Meyers lemons, mandarin oranges, and key limes. Here we’ll discuss how you can grow key limes in containers.
Citrus Growing Conditions
Citrus is a subtropical fruit that includes oranges, grapefruit, lemons, and limes. Unlike some fruit trees, most citrus is self-fertile, so only one tree is needed for the fruit to produce. On average, citrus trees begin to produce fruit once they’re 3-5 years old. Citrus also needs a certain level of accumulated heat to ripen.
If you live in hardiness zone 8 or above you should be able to grow citrus without having too much of a problem. Citrus trees are very frost-sensitive and need to be protected or moved (if in pots) when there’s cold weather. If winter nighttime temperatures where you live are consistently below 35°F then you’ll need to be able to move your trees indoors. If you only have occasional cold temperatures, then you’ll want to cover your citrus trees with frost blankets.
Image Credit: fast-growing-trees.com
Florida is home to the Key Lime Pie, but ironically the tiny yellow fruit hasn’t grown here commercially for decades. Groves were commercially grown in the Florida Keys, and the industry peaked in the 1920s until 1926 when a hurricane wiped out the groves. They were never replanted. While the largest commercial producer of key limes is now Mexico, there are still a lot of Florida homeowners who grow their own key lime trees.
Key limes are different than Persian limes that are typically found at the grocery store. Key limes are smaller, roughly 1-2 inches in diameter. They are also round and yellow when mature. The peel is thin and smooth and the juice is more tart.
The Key Lime is more cold-sensitive than other citrus trees due to how acidic they are and tends to be injured or killed when temperatures drop below 32°F. Key lime trees like well-draining soil and extensive periods of flooding can kill the tree. Grown in full sun, citrus trees need quite a bit of heat to set quality fruit. Fruit ripens about 5-6 months following flowering. Trees are small and thorny with small pale green leaves. The flowers bloom primarily in the spring, followed by summer fruit.
Grow Key Limes in Containers
You would grow key limes in containers similar to other citrus trees. There are a few things to be more aware of when growing in containers versus in-ground planting. Trees have more room to grow in the ground, however, sometimes there isn’t enough space to allow that, and container gardening can still give you the opportunity to grow some of the fruit you enjoy. Trees planted in containers will not become as large or produce as much fruit as trees planted in the ground. However, if you live further up north you’ll be happy to be able to bring them indoors when it’s cold outside.
Citrus trees have wide, strong root systems that help them gather moisture in hot climates. Keeping this in mind, when you choose a container you should make sure it has a larger diameter to allow your tree to spread its roots at the surface level. Most tree roots are located in the top 6 to 24 inches of soil. A pot that is 28″ or larger in diameter should be used. Drilling additional holes in your pot might be necessary for drainage. If you live in an area that gets cold in the winter, consider how you will move the pot.
When planting your tree in your pot you’ll want to make sure you plant it at the original soil level. This will ensure that the graft union is above the soil line. Fruit trees are typically grafted to a rootstock, about 4″ to 8″ above the rootball.
Potting soil should always be used for pots and containers. Regular soil compacts. Potting soil is different in that it includes material that allows for aeration and drainage. Materials such as perlite, vermiculite, or peat moss should be mixed into your soil.
When choosing a location for your tree, you should select a spot that gets 6-8 hours of sunlight a day. They can tolerate some shade in hotter zones but thrive in full sun. Potted plants do enjoy a daily misting for humidity. Keep in mind that shadows are longer during winter months, so you’ll want to be mindful of how close you keep your trees to the south side of your yard.
You’ll want the top 2-3″ of your soil to completely dry out between watering. This can be anywhere from once a week to every day. Once the soil dries out on top, you should water until you see water escaping the drainage holes at the base of the pot. Citrus roots like moist but not soggy conditions. The watering needs of citrus will be different when they are in containers because roots will dry out more quickly. A moisture meter can help you determine when it is time to water.
Pay attention to the foliage. Wilted leaves that perk up after watering meaning you should be watering more often. If your leaves are starting to yellow or curl it could be a sign that you’re watering too much (though yellowing can also be a nutrient deficiency).
Trees grown in containers need more fertilizer compared to trees that grow in the ground because their environment is very self-contained. Although there are many varieties of citrus trees, their needs are about the same: nitrogen, phosphorus, potassium, sulfur, and calcium. Nutrients that are required, but needed in less abundance, include iron, zinc, magnesium, copper, molybdenum, manganese, chlorine, and boron.
The amount you apply will depend on the type of fertilizer as well as the size and age of the tree. Citrus grown in containers should be fertilized every other month during the growing season. Organic, liquid seaweed can be sprayed on the foliage on a monthly basis. Liquid seaweed spray contains 60+ trace minerals and also helps the tree to become resistant to disease.
Any branches that start to grow below the graft union should be cut off because they will steal nutrients from the primary trunk of the tree. Dead branches should also be pruned. Citrus can be pruned for size and shape, but it isn’t necessary. The best time to prune is in the spring after the last freeze has passed but before new growth appears.
Key Lime Pie Recipe
Key limes can be used for desserts, drinks, and adding acidity to recipes such as salsa, guac, and fish. But they’re known famously for pie. I didn’t think this article would be complete without a key lime pie recipe. 🙂
Pie Crust Ingredients:
- 12 graham cracker sheets
- 4 tablespoons melted butter
- 1/2 cup sugar
- 4 egg yolks
- 1 (14 oz) can sweetened condensed milk
- 1/2 cup fresh key lime juice
- 4 eggs whites
- 4 tbsp sugar
- 1/4 teaspoon cream of tartar
- Preheat your oven to 350° F. In a food processor, pulse the graham crackers until they are fine crumbs. Add the melted butter and sugar and pulse to combine.
- Press the graham cracker mixture into a 9-inch pie plate or tart pan. Bake the crust for 10 to 12 minutes, until golden. Remove from oven and let cool slightly.
- While the crust is baking, whisk together the egg yolks, condensed milk, and Key lime juice until blended. Pour the mixture into the crust and bake for 15 minutes. Remove from oven and let cool.
- In a stand mixer or large clean bowl, whip the egg whites until stiff peaks form. Add cream of tartar. Slowly add the sugar and whip until the egg whites are in stiff peaks. Spoon the meringue over the cooled pie filling.
- If you want to toast the topping, use a kitchen torch to lightly toast the outside of the meringue or place it under the broiler on high. Watch it carefully! It will brown quickly.
Thanks for the article. I live in St. Louis and grow a key lime in a pot. It is about 5 years old. It bore fruit last year for the first time. It loves our hot summers and high humidity. Last year I had about 15 limes. This year I see about 50 blossoms .
The pies last year were great! Can’t wait to try this years crop.
Jerry – that’s awesome to hear! I’m so glad you’re enjoying the fruit of your potted key lime tree!
We’ve had one for 3 years now and never any fruit. I’m hoping to see some next year at least. So impatient! Lol
Hi! – Thank You for providing your info on growing Key Limes in pots. I am a native to Fort Lauderdale, and I too, grew up with a big Key Lime tree in the back yard, plus avocados, Japanese plums and a huge tangerine tree in my front yard, and towering mangoes and coconut trees all over my neighborhood. But I moved away over 15 years ago and Really missed my Key Limes. I am moving back to Tampa and will certainly give them a try in large pots! Thank You again for the inspiration and tips!!!!
Thank you! The trees you had in Fort Lauderdale sound amazing, super excited you can have some of that in Tampa!
My key lime has been brought in side and I am using a grow light, the leaves are yellow so I’m thinking its missing nutrients, not over watering. Looking for a citrus tree fertilizer.
Hi Paula, I just purchased an organic citrus fertilizer last month for my potted citrus plants. Here’s the link: Down to Earth Organic Citrus Fertilizer Mix
Many years ago, I had a large Key Lime, grown from a seed, that never bore fruit. My grandmother told me to drive a “cut nail” -an iron, concrete nail, into the trunk. I did. It started earing like crazy and never stopped. The same think happened to me later at another location. The same solution worked.
Interesting information! Thank you for sharing, James!
Very comprehensive and easy to understand. I’m growing a key lime in a container just North of Sacramento, CA. With a lot of nurturing in the winter I have harvested healthy crops for the last three years. This year my tree got leggy and, while it produced lots of fruit, it doesn’t look that healthy. I’m trying to rejuvenate it and will certainly use your ideas. Thanks for your help.
Hope you’re able to rejuvenate your tree, Donna!
I have a 32 year old key lime tree in Northern Virginia I bought on Marathon Key in 1990. It winters in my garage and produces plenty of fruit every year.
I love this! Thank you for sharing!
I live in northwest Nebraska. I started a key lime tree from seed in 2015. It is in a pot and seems to be growing very well no flowers or fruit yet. Winter is on the way. Can I still use the tree fertilizer on it this late in the year? Thank you
In general, you should fertilize your citrus about once every one to two months during active growth (spring and summer) and once every two to three months during the tree’s dormant periods (fall and winter). So I don’t think that should be an issue.
Thank you! I got my tree as a gift last Christmas and live in zone 5b. It bloomed last spring, but when I took it outside, it dropped ALL of its leaves and I thought it was a goner. So I took off all of the immature fruit so it would grow leaves instead. Luckily it survived. Because of your article, now I know I will have to be patient for this year’s fruit to ripen. 4-6 months is a LONG time! I also know that I am probably under watering. Thanks for your wonderful information!
I’m glad your tree is doing better! Thank you for stopping by, Angie!