Growing Your Indoor Key Lime Tree

• WHAT TO LOOK FOR: If you purchase your Key Lime from a nursery, look for plants that are at least 2 to 3 years old. Key Lime Trees are also suitable as houseplants. They can be maintained at 3 to 5 feet tall and if you have the knack, Key Lime trees make wonderful Bonsai specimens.
• SOIL: Like most houseplants, citrus prefer a slightly acid, all-purpose mix, which you can get by using a peat-moss based growing mix. (Remember, you get what you pay for, so don't go for the cheap products.)
• TEMPERATURE: Lime trees thrive in a normal temperature range of 70 degrees during day to 55 degrees at night. TIP: Though the plants are evergreen they will go into dormancy and stop growing below 54 degrees F.)
• LIGHT: Set your lime tree in full sun from a southern exposure. Trees need lots of light. If that's not possible, supplement the light by installing 40-watt fluorescent shop lights above the plants -- especially important in the winter, when they need 8-12 hours of light.
• MOISTURE: You'll need to keep the soil evenly moist and since most interiors are quite dry, mist your plant often -- daily if you can. Give your lime tree a shower occasionally. They loved to be wiped down gently with a sponge.
• POLLINATION: When you grow plants indoors, bees and insects can’t pollinate them. So you need to use a paintbrush or cotton swab to rub pollen within the flower. Sometimes they will produce fruit without doing this, but it's a good idea to increase your chances!

Live In A Cold Zone?

• First and foremost, avoid planting a dwarf citrus tree in the ground - especially if you are north of USDA Plant Hardiness Zone 9. Can it be done? Of course, there are exceptions to every rule. But don't forget about those weekend trips in the fall, about the time the first hard freeze arrives. When you're gone, will your neighbors be willing to go through the trouble of protecting your citrus tree? Planting a dwarf Key Lime Tree in a container helps you to avoid this. And it allows you to interior-scape during the cold months. 
• Container size is very important. Choose a container that is ample for the tree. A 10-15 gallon container will allow for a 10-feet-tall tree under perfect conditions. Under average conditions, a tree can reach 7-8 feet in a pot this size. Allow for a few years of growth, so that you are not repotting every spring. A 10-15 gallon container is excellent for a 3-4 year old specimen. And make sure your container has a drain plug. 
• To pot a Key Lime citrus plant, start with a layer of stones or broken pottery, then add well-draining soil. Make sure you put in just enough soil so that the root ball is barley covered. If the trunk is below the soil line, it will rot. 
• To keep the tree small, allow it to be root bound. But make sure there is enough soil on the sides of the pot so the tree can absorb water. 

• Q.  Can I grow a dwarf Key Lime tree at my home in the northeast?

   A.  Dwarf citrus trees can be successfully grown in containers throughout the United States. For best results, place your dwarf Key Lime trees on a porch or patio in the spring, summer and early fall.  As winter approaches and temperatures begin to drop in the thirties, bring your trees indoors and place in a window with a western or southern sun exposure. The fruit will begin to ripen as you bring the trees indoors. Within a couple months, the trees will bloom again as they’re moved back outside for spring. Sometimes it will actually blossom before they go outside.