Growing a lemon tree is rewarding for gardeners of all skill levels. Aromatic leaves make the lemon tree an excellent choice for container gardening, even indoors. Outside, the lemon tree is a prolific producer of fruit while attracting beneficial insects such as bees to the garden. Propagation of lemon trees is possible by seed, cuttings, layering, budding or grafting. Budding and grafting require compatible rootstock and scion wood. Growing from seed, cuttings, or by layering is much easier for the average gardener to successfully manage.
Lemon seeds can be successfully propagated, even from store-bought fruit. There is a drawback to using seed harvested from commercial fruit. The parent plant may be a hybrid, with a greater chance that the seed will produce a sterile tree. Even so, the plant will be aromatic and attractive, making it a worthwhile endeavor. Whenever possible, harvest fruit and seed from a known tree to ensure the best results.
Lemon seed deteriorates quickly. Remove the seeds from the fruit. Rinse them well with plain water. Do not allow the seed to dry. Expedite germination by abrading the seed coat with fine sand paper, or nicking it with a knife or pin. Place the seed in a small container of growing medium or seed starter mix. There are commercially mixed citrus growing soils available, but any well draining potting soil will do. Some gardeners place the seeds on moistened paper towels sealed inside a zip lock bag. This allows closer observation of the seed as it swells and germinates, but is not a necessary step. Placed in a warm spot, or given bottom heat, the seed will sprout in about one week.
Cuttings are another reliable means of propagating lemon trees. Take stem cuttings of 6 to 8 inches from new green growth. Remove all but the top two leaves. Apply rooting hormone to the base of the cutting, tapping off excess. Plant the cutting in a sterile growing medium or potting soil. Use a pencil, chopstick or other device to poke the hole into which the cutting is placed. That way, the hormone will not be dislodged in the planting process. Water well to firm the soil. Place the potted cutting in a sealed plastic bag to keep the humidity high. Fastest growth will be achieved in stable temperatures between 70 and 80 degrees Fahrenheit, or with the application of bottom heat.
Propagation by layering has the advantage of providing larger, robust plants in less time than is possible with seeds or cuttings. Select a branch of new growth with a diameter of approximately ½ inch. Remove a ring of bark from the branch ½ inch in width. Apply rooting hormone to the wound. Wrap moistened sphagnum moss around the treated area. Cover the moss with plastic wrap. Tape this bundle securely to retain the moisture. Roots will grow from the wound site while the parent plant is still providing nourishment for the branch. Cut the new plant from its parent when the roots have developed sufficiently to support it.