Lemon and other citrus trees grow well in the ground in warm areas of southern Texas, Florida and California. In other parts of the country, the plants are well adapted to growing in containers. You can germinate seeds from store-bought lemons to create new container or ground trees quite easily. Most lemons sold in the store are hybrids, so the fruit that your tree produces will not be similar to the store fruit. Lemon trees grown from seed are sometimes more sickly and spindly with thorns. The trees will not produce fruit until they are at least 10 to 15 years old.
Soak lemon seeds in a glass of warm water for 24 hours to promote germination. Skim off any seeds that float on top of the water. These seeds will not germinate and are not viable.
Fill a seedling tray with peat moss. Soak the tray so that it is as damp as a wrung-out sponge.
Place seeds in the seedling tray and cover them with peat moss. Plant seeds twice as deep as their diameter.
Place a plastic bag over the seedling tray and place the tray in a sunny windowsill out of direct sunlight. Check the moisture of the plants daily and water when the soil becomes dry. Remove the bag when the seeds sprout.
Move the lemon trees to a 4 inch diameter container filled with peat moss when the plants outgrow the seedling tray. Fill a 4-inch pot 1/3 with peat moss. Place the seedling's root ball in the pot. Fill in the sides and over the top of the seedling with the peat moss. Water until the soil is as wet as a wrung-out sponge.
Transplant the lemon tree into a larger pot once it outgrows the 4-inch container. Or move the seedling into the ground if you live in a warm enough climate. Select a citrus potting mix for container plants, or plant your tree in well-drained soil with full sun.
Water trees in the ground with 1 inch of water every seven days. Stick your finger into the soil of container plants up to your second knuckle to check the dampness of soil; water any time the soil is dry. Soil should never be soggy, but should remain as damp as a wrung-out sponge.
Fertilize each spring with an acid-based fertilizer formulated for roses and azaleas. Spread granular fertilizer evenly over the root zone, or apply liquid fertilizer according to the package directions. Directions will vary among brands.