Lime trees are a novel addition to a garden, but are only easy to grow in tropical or semitropical climates. If you live in a location with cold winters and hot summers, you will have to do a lot more work to successfully grow a lime tree. A lime tree works well as an ornamental plant, as well as a fruit-bearing plant. Growing the tree from a seed is more difficult than planting a sapling, and it will take longer to produce fruit as well.
Obtain the lime tree seeds. You can do this by ordering lime tree seeds online in packets, or searching for a lime seed in a local or store-bought lime (which may be difficult because many store limes are propagated seedless). Key and Kaffir lime trees have ideal seeds for planting. Rinse the seed thoroughly if removed from a fruit, then let dry on a paper towel.
Prepare a soil mixture of equal parts potting soil, peat moss and sand, and fill small planting pots with the mixture (pots the size of a yogurt cup, up to a regular planter, will do).
Insert your finger into the soil mixture down about 1/2 inch. Then add two lime seeds into the hole and lightly cover with some more soil, pressing down lightly to make sure they are packed in. Place these planters in a sunny area so the soil can be kept warm and moist. Times vary, but you may see the seed germinating as early as 7 days after planting.
Pick an outside spot in your yard for the lime tree as it grows a couple of inches. It is important to keep it in the pot if you live in an area that gets frosts, because you will have to bring it inside at this time. As the plant grows, remove any small extra branches that are within 8 inches of the soil. This will help tailor the lime tree to one large single stem, but as it grows larger, extra branches can be left on.
Water the lime tree regularly enough that the soil is kept moist but not soggy, depending on the sun in your location, every 2-3 days. Keep it in a well-draining pot, for it to remain appropriately moist but not too wet.
Protect the lime tree when the temperatures begin to get cold. If the temperatures drop below 50 degrees Fahrenheit, bring the lime tree back indoors in a sunny place. You may need to decrease the amount of watering since it won't be in as many hours of sunlight.
When the seedlings have reached 6 inches tall, transplant them to larger pots. This can happen in as soon as 8 weeks. Fertilize the lime trees a couple of times a year with citrus tree fertilizer.
Be patient, as a lime tree may blossom and produce fruit within a couple years, but it could be up to 8 years before you see any fruit. Keep the branches in check by pruning any diseased, dead or awkwardly growing branches (any growing straight up or down). Bring your plant outside anytime the season is warm, as it needs to be pollinated in order to produce fruit.