There are various methods of propagating lilies. In this article we shall briefly discuss two means - propagation by stem bulblets and propagation by stem bulbils.
Several types of lilies develop bulblets beneath the soil surface on the stem a little higher than the central bulb. There are others that turn out stem bulbils in the leaf axils of the plants. In fact, it is possible to induce bulbil production in majority of the lilies. When we use the term bulblet, we actually refer to a little bulb or bulb-like formation particularly that grows in the leaf axils, like in the instance of the tiger lily. Often the bulblet substitutes for a flower, like in the case of onions. Bulblets may also develop on the part of the stem that lies underground, such as in the stem-rooting types. The number as well as the size of these bulblets are subject to the lily species or cultivars and also the vigour of a particular bulb. In fact, the stem of a robust bulb can produce as many as a dozen or sometimes even a greater number of bulblets. These bulblets are wholly developed small bulbs having scales as well as roots that are ready for a self-sufficient life when the stem wither away. In fact, the size of some bulblets may even be similar to that of a small walnut, but majority of them are about the size of marbles. Nevertheless, it is possible to grade down the relatively larger bulblets to tiny ones by removing a few delicate, tiny scales. On the other hand, you can also pot up the extremely minuscule bulblets and persuade them to fatten up using utmost care. It is worth mentioning here that the number of such bulblets that you can harvest from the underground part of the lily stems is directly associated with the amount as well as robustness of the stem rooting. In order to augment the numbers of bulbs that you can harvest from the buried portion of the stem, and also more considerably, by their volume and weight, you need to encourage stem rooting. Initially, you can do this only if you provide an open, grainy soil rich in humus content and plant the bulbs no less than 10 cm to 15 cm (4 inches to 6 inches) higher than their noses. At the same time, you should ensure that the soil remains moist, but not soggy. It is possible to increase the stem rooting activity considerably by providing humus mulches towards the end of spring onwards. It has been found that lily species like Lilium lancifolium, Lilium regale and Lilium henryi along with their hybrids produce some of the most exceptional bulblets, which can be successfully grown into individual plants. In addition to these lilies, even Lilium speciosum, Lilium auratum, Lilium longiflorum and Lilium davidii often produce robust bulblets. On the other hand, the stems of Lilium dauricum may travel some distance underground after emerging from their bulbs and they produce bulblets the length of their underground stems. Lily species having stoloniferous stems, for example Lilium duchartrei, will normally develop two to three bulbs the length of their meandering underground stem. If all things are favourable, these bulbs will replicate the same process effortlessly giving rise to a clump of lilies bearing beautiful flowers in just a few years.
Many of you may possibly be wondering what bulbils actually are. Simply speaking, they are progenies of their parent plant and similar to seeds, they also reproduce provided the conditions are favourable and give rise to new independent plants. Since bulbils propagate very easily, it is beneficial to learn how to propagate new plants from bulbils. In fact, they make propagation easier since majority of them can be harvested when they have become mature. Subject to the type of lilies or other plants, the bulbils may bear resemblance to little buds akin to nodules and appear either individually or in clusters. They may emerge from the base of a plant that is moving upwards or also be aerial, appearing in the plant's crown. Some of the plants that produce bulbils include agave as well as many members belonging to the onion family, counting garlic. In fact, the Egyptian walking onion is also considered to be a tree, precisely speaking a top-setting onion. It has been named "walking onion" owing to its exceptional capability to self-propagate. The mature Egyptian walking onion plant grows bulbils at the top of their stalk, which is followed by a small flower stalk. This flowering stalk also generates bulbils, which weigh down the plant, making them touch the ground just a few inches away from their mother plants. When the bulbils come in contact with the ground, they start sending out roots and eventually grow additional plants - reproducing naturally. It is reasonably easier to propagate plants from bulbils. They can be separated from their mother plant without any difficulty and directly planted into the soil. If you plant the bulbils towards the end of summer, it allows the plants enough opportunity to grow strong root systems ahead of the winter. While propagating plants from bulbils it is important that you ensure that they are provided with lots of water regularly, as this will help the new bulbils to establish robust roots. The tiger lily (botanical name Lilium lancifolium), also known as L. tigrinum, is possibly the best example of the method involving stem-bulbil production increase. This plant produces little, dark-hued buds in its leaf axils and these eventually enlarge to turn out to be mini purple-black bulbs. Occasionally, they are found to produce leaves and roots even before they become completely mature and drop to the ground. Generally, most of the leaf-axils are content with bearing a solitary bulbil, but sometimes you may also find a leaf-axil producing as many as two to three bulbils. If you leave them undisturbed and follow their own mechanism, they will drop on the ground sooner or later and drag themselves into the soil. On the other hand, if you are able to handle them just prior to them dropping on the ground, you can possibly harvest about a hundred bulbils from just one lily stem. Aside from the tiger lily, there are a number of other lily species, including the Lilium bulbiferum, which behave in a similar manner. In the case of L. bulbiferum, a number of clones are found to be distinctly more adept as well as productive compared to others. In addition, the rare, exquisite, yellow trumpet lily (Lilium sulphureum) as well as the white Lilium sargentiae produce bulbils as well, at times very efficiently. On the other hand, the Asiatic lily, Lilium davidii, may also produce bulbils by itself or you may also stimulate these plants to produce bulbils. Similarly, L. davidii hybrids may also produce bulbils freely or they may be induced to produce them by removing their flowering tops prior to the plants developing small buds. If you harvest the bulbils and pot them up ahead of late summer, a good number of them with reasonable size can be grown into new robust plants that would produce one or several flowers in the subsequent summer. You may start a partially-intensive system with the aim of achieving the maximum potential increase by bulbils for any specific lily type. Once you have ensured that the selected clone is capable of producing bulbils, you can seek to propagate the maximum possible number of small bulbs by collecting the bulbils and also by breeding little bulbs from scales. When raised under cool glass, these bulbs will generate thin stems in the next season. Provided you grow them robustly, apparently they can normally produce bulbils in great numbers, particularly if you pinch off the flowering buds or the developing tips of the stems quite early. After you have harvested the crop of bulbils in summer, you can easily continue with the production process till you obtain the desirable number of plants.