Pollination and Seed Collection of Lithops from Seedling Management
The editor brings you the relevant experience of Lithops, a type of succulent plant, including the pollination, seed collection, and seedling management. Here is the detailed introduction.
Lithops, with its unique shape and colorful patterns, has won the favor of many succulent plant enthusiasts and has become one of the very popular collections of succulent plants. Introduced into China since the 1950s, domestic enthusiasts have basically acquired most of the original species, especially in recent years, more varieties have been introduced directly from the United States and some European countries. Whether it is the introduction of original species or breeding based on hybridization, enthusiasts need to understand the characteristics of Lithops seed propagation to achieve a higher seedling rate.
Currently, most enthusiasts in China focus on caring for adult Lithops, although they are willing to get involved in seedling cultivation, the difficulty is considerable, which has discouraged many friends. The reason is that although Lithops belongs to succulent plants, the process of seedling cultivation is quite different from that of typical succulent plants like cacti and lilies. The main process and key points are as follows:
1. Parent Selection and Pollination
Most Lithops varieties bloom in autumn, with only a few, like "Quyu," blooming in summer. Generally, the earliest to bloom in autumn is "Weuwenyu," followed by "Hewenyu, Hualunyu, Chaogongyu, Lihongyu, Fulaiyu, Zixun, Rilunyu, Qingciyu," and the last to bloom are "Lanxingyu, Taiguyu, and Jushuiyu." The blooming period of different varieties may vary under different cultivation conditions. Overall, when pollinating Lithops, it is best to choose parents that are closely related to increase the germination rate of the offspring. Distant hybridization may lead to variegation or even seed dormancy. For individual plants, Lithops individuals over 5 years old are almost all good parents, with seed yields reaching several hundred (varies by variety). Pollination between different lateral buds of the same plant generally does not work, and it is necessary to choose individuals from different sources, so it is essential to deliberately choose two or more plants of the same kind when purchasing Lithops.
Lithops has a long blooming period, with the longest being "Huangweiyu" (up to about 10 days), with the 3rd to 5th day being the best period for pollination. At this time, the pollen is mature and the stigma begins to secrete sticky fluid. They usually bloom around 4 p.m., making it the best time for pollination. Pollination can be done by using a cotton swab to collect pollen and apply it to the stigma of the female parent. If intentional hybridization is desired, all the stamens of the female parent should be removed on the first day of flowering, and then the stamens or anthers of the male parent can be applied to the stigma of the female parent using an ophthalmic forceps. Successful pollination can usually be seen when the stigma of the female parent turns yellow (covered with pollen), and the next day, the flower begins to wilt gradually, which is an important indicator. Pollination of Lithops is generally easy, with a large amount of pollen and a high success rate.
2. Fruit Maturation and Seed Collection
After pollination, the flower begins to wilt, the petals gradually dry out, and the ovary starts to swell. Usually, within 2-3 weeks after pollination, the petals are mostly wilted, and even dried, at which point the dried petals should be gently removed with a pair of forceps to expose the fruit. During this period, sufficient fertilization, water management, and sunlight are required, especially sunlight is crucial for fruit maturation. Removing the petals allows better sunlight to shine on the fruit, causing it to expand rapidly and become thick, with the fruit volume and number of seeds at least doubling compared to fruits with petals left on, a practice commonly known as the "sunapple" theory.
The fruit matures around the beginning of spring, with the speed of seed maturity varying depending on the variety and cultivation environment. A typical sign is that the fruit becomes dry, at which point it can be harvested. The harvested fruit should be cut from the base of the stem, dried in a shaded and ventilated area, and stored in sulfuric acid paper bags. Dry fruit will crack when it encounters water, causing the seeds to scatter, so it is best not to water from above during the fruit maturation period. This period also coincides with the peeling period of Lithops, so it is appropriate to reduce watering, ensuring sufficient "backflow" of nutrients from old leaves to new ones and ensuring the safety of the fruit. After collecting the fruit, it is best not to rush to remove the seeds from the fruit but rather store them together in paper bags to promote post-ripening of the seeds, which can be sown in the autumn of the same year. Spring sowing is not recommended.
3. Preparation of Planting Materials
The topsoil for Lithops seed sowing should be fine-textured akadama soil that has been sieved, with particle size not exceeding that of millet. The lower layer of soil should be mixed with some peat or rice husk ash on top of akadama soil to increase nutrition, with slightly larger particles but still not exceeding half the size of a grain of rice. There are no strict requirements for the flower pot, a plastic pot will do, and it doesn't need to be too deep. Both the soil and the pot should be disinfected, with the simplest method being to soak in a potassium permanganate solution: first, fill the pot with the lower layer of soil, about 2/3 of the pot, and then cover it with a 1cm thick layer of topsoil. Level the soil surface and immerse the entire pot soil in boiling water infused with potassium permanganate solution, to a depth of 1/3 of the pot. The disinfectant solution will be drawn into the soil through the holes in the bottom of the pot. The concentration of potassium permanganate can be observed by the color of the solution, generally a clear deep purple is fine, too concentrated and the bottom of the container cannot be seen. Boiling water helps potassium permanganate to exert its disinfecting effect.
When the temperature of the potassium permanganate solution in the pot drops to room temperature and the soil is fully soaked, a little water can be sprayed on the surface of the pot soil with a sprayer to make it flat and clean for sowing. Adding a small amount of long-acting antibacterial agents, such as thiabendazole or carbendazim, to the spray water will further help the safe germination of seeds.
4. Sowing and Germination
Sowing is done in the middle to late September of autumn (this may vary by region), with the stored fruit cut open 1 week in advance, the seeds carefully removed with forceps, impurities removed, and then sown. Dense sowing is best to increase germination rates. Different varieties should be sown separately, not mixed, as the germination times of different seeds vary, making management difficult.
When sowing, a hard paper trough can be made, the seeds placed in the trough, and then gently scattered onto the surface of the pot soil using a forceps to tap the back of the trough. After sowing, cover with a transparent glass board to retain moisture, using scattered sunlight or fluorescent lights as a light source. Healthy seeds will start to germinate on the 3rd day after sowing and finish by about the 10th day. After most seeds have germinated, the glass board should be gradually removed: start by propping up one corner with a toothpick, then another corner a week later, gradually increasing ventilation and reducing humidity. After 1 month, the glass board can be completely removed. At this point, lighting can be gradually increased, and water can be supplemented with a spray every evening (adding a small amount of antibacterial agent is recommended).
5. Seedling Management and Transplanting
After germination, Lithops seedlings are very susceptible to moisture, darkness, and mold, so it is important to gradually remove the glass board, maintain sufficient and gentle lighting, and this is also where Lithops differs from other succulent plants in seed sowing. Fungicides are very important, and it is best to choose a variety of types and use them alternately to avoid resistance to the fungus. Adding some to each watering can ensure a higher seedling rate but should not be too concentrated.
Usually, after sowing in autumn, the seedlings begin to peel and show some shape during the Spring Festival. At this point, they can be transplanted to initially screen the varieties, removing weak, deformed, and poorly patterned individuals. For beginners, it is advisable to delay transplanting until the following spring to increase survival rates.
The soil used for transplanting is similar to that for sowing, as the seedlings are small and cannot tolerate large particles or high fertility soil. When transplanting, the roots can be trimmed, there is no need to be stingy with them, leaving about 1cm of root for each seedling. After transplanting, do not water for 2 days, and then gradually spray water in the evening (adding fungicides) after 3 days. Gradually expose to light, and by about 1 week, new roots will have emerged, entering normal management.
The detailed introduction provided above on the pollination, seed collection, and seedling management of Lithops is for reference by netizens.