Want to propagate a plant? Don’t have to wait for the seeds~
In one of China’s classic and beloved tales, there is a famous monkey character called Sun Wukong. He, spiritually as a student and physically as a bodyguard to an esteemed monk of the Tang Dynasty, accompanied his master on his journey to India in seek of authentic and original Buddhist texts. Sun had a formidable repertoire of powerful spells, one of which is the ability to tear off a few of his body hairs, and, with a puff, turn them into replicas of himself. From the point of view of humans, or indeed, most animals, this is an incredible capability, but to many plants, this is nothing special. Cut a branch off a Thai willow, and (with or without a puff) plug it into the soil, you’ll get another Thai willow. ‘A flower may die regardless of how much care you give to it, whereas a willow branch you carelessly throw away may turn into a full-grown tree.’ – so goes the Chinese saying.
Unlike most animals, which reproduce sexually, many plants can reproduce either sexually or asexually. In the past week or so, I have practiced a number of methods of propagating plants. Apart from the Thai willow, many have been multiplied by taking cuttings from a mother plant and cultivating them in pots, such as Javanese treebine, Plumeria, Alamanda, Congea, Gliricidia, and so on. In fact, using cuttings is preferred whenever it’s possible, due to the hassle-free nature of its application. Normally branches which have acquired a sort of ligenous bark are suitable candidates, instead of green young ones; and one should also take the precaution of ridding the branches of all its leaves, because they would help with nothing but let go water during the initial stages of growth. Although taking a part of a plant and growing it into a whole new one doesn’t seem as mysterious as Sun Wukong’s feat, if one ponders on it, it’s actually a remarkable phenomenon. Think about, for instance, how scientists have been trying desperately to induce adult animal cells to acquire a stem cell-like potency, so that they could be used to replenish damaged body parts, but with limited success; yet for plants, it can be achieved fairly easily.
If using cuttings fails, another convenient and asexual way to propagate plants would be to force a branch into contact with soil, while it’s still connected with the main plant. The chances are that roots may develop at the point of contact, after which one can cut it off and grow it independently. The ones I have tried this method on are Bauhinia aureifolia, the one with beautiful golden leaves, Clerodendrum, and Uvaria.
Still another asexual method, for a bushy plant, is to dig it out, break it up and put the divided lumps back into the soil. I experimented this on Stevia rebaudiana, an interesting plant with leaves that contain a glycoside that is 300 times sweeter than sucrose and that can be used as a sugar substitute. Noticeably, some of the branches that touch the ground have made roots, therefore I imagine they could potentially be multiplied by the previous method.
As easy and quick as cloning plants may be to humans, it’s not applicable to every plant species. After all, sexual reproduction is the predominant means of passing on your genes in the world of multicellular organisms. I sowed the seeds of the a few plants, like papaya, coffee, yellow cashew and so on. But more excitingly, I watched Eric manually pollinating two species of orchid, which he mentioned in a previous blog, and the orchids really live to their fame of having flowers with intricate structures that are tailored for very specific pollinators.
So, even though we don’t have the fortune to meet Khun Sun in person, that shouldn’t be too much of a pity, since we have the plants around us to marvel at, for the array of ways through which they can reproduce themselves.
Yichao, Tropical Gardening School student from Shanghai