UMBELLIFERAE Centella asiatica Cultivation Methods and Precautions, and the Feng Shui Significance of Yellowing Leaves

Centella asiatica is slender and easy to grow, with a lovely form; the plants cluster together into a clump, dotted with emerald green leaves, giving it good ornamental value, making it very suitable for household pot cultivation. So, how do you grow Centella asiatica? Below is an introduction to the cultivation methods and precautions for Centella asiatica.

How do you grow Centella asiatica?

Best propagation time: mainly propagated by division or cuttings, mostly carried out from March to May each year; cultivation is easy, keep the growing soil moist, and roots will form in about 1-2 weeks. Seed sowing can also be used for raising seedlings. For the growing medium, a mixed substrate made of leaf mold, river mud, and garden soil can be used, with their proportions by volume being 0.5:2:2.

Best growing soil: Centella asiatica is not strict about soil requirements; whether yellow loam, red loam, or black loam, it can even grow in poor soil. However, its drought resistance is not strong, and it is most suitable for growing in fine, slightly acidic, moist, low-fertility loam. Centella asiatica is suitable for fertile, loose soil with high water absorption and good water retention, and can also be cultivated in moist riverbanks, swamps, grasslands, or low-hardness freshwater.

Growing humidity requirements: Use a medium with good water retention and keep it moist at all times. The amphibious Centella asiatica is commonly found in aquatic ponds, wetlands, and other spaces, and water trays and aquariums are also very suitable.

Best growing temperature: Centella asiatica likes warm and humid environments but is not cold-tolerant. It grows well in a temperature environment of 10-25°C. When the summer temperature rises above 32°C, growth stops, and in winter the temperature must not be lower than 5°C.

Best growing light: Centella asiatica is shade-tolerant, preferably with partial sun or in a shaded place, and avoids direct strong sunlight. The more shaded the environment, the more easily the plant's leaves rot. Centella asiatica does not compete for light, but if it receives 4-6 hours of scattered light every day, or is given 8-10 hours of artificial light, it will grow even better.

Precautions for growing Centella asiatica

Fertilizer application: Centella asiatica has a relatively high demand for fertilizer; during the vigorous growth stage, apply fertilizer once every 2-3 weeks. If planted in pots or containers, then only a small amount of fertilizer is needed, such as the quick-acting fertilizer Hyponex No. 2, which can maintain fertilizer efficacy in water for a relatively long time, ensuring the water quality is slightly acidic or neutral.

Key watering points:

1. Centella asiatica likes a relatively moist growing environment. Because it has many leaves and a high transpiration rate, in summer it should be sprayed with water frequently to maintain relatively high air humidity, and the leaves should be kept clean to facilitate photosynthesis. In winter, the potting soil should preferably be on the dry side; watering should follow the principle of preferring wet over dry, and waterlogging should be avoided, otherwise root rot easily occurs.

2. Tap water in the north should be left in the sun to stand for 1-2 days before use. During the growing period, water once every 2-3 days to keep the potting soil moist. For water culture, change the water once every 7-10 days in spring and summer, and once every half month in autumn and winter.

3. If growing in water, be sure to change the water once a week and add a special nutrient solution for foliage plants. If using soil culture, then be sure to retain water for the long term. Water once every morning, but do not overwater; the degree should be that water flows out from the bottom hole, ensuring the potting soil is thoroughly wet.

Pruning essentials: Centella asiatica generally does not require extensive pruning. When the leaves are too dense, promptly remove withered bottom leaves and outer old leaves and diseased leaves to improve light and ventilation conditions. In spring, when the pot is full of roots, repot and divide and reshape the plants.

Potting soil replacement: In spring, when the pot is full of roots, repot and divide and reshape the plants. If the plant grows too tall, it should be pruned back to encourage new shoots to sprout from the base of the stems and leaves. Centella asiatica does not need a very large pot; a relatively large bowl can also be used for planting, and a narcissus pot will also do. When planting, it can be planted flat, and the rhizomes should be covered so that they are not visible; be sure not to plant too deep. Then place it in a semi-shaded place for a week and wait for new leaves to grow before exposing it to sunlight.

Propagation essentials: This plant is mainly propagated by division or cuttings, mostly carried out from March to May each year; cultivation is easy, keep the growing soil moist, and roots will form in about 1-2 weeks.

Pest and disease control: Centella asiatica has very few pests and diseases. It has strong growth adaptability and requires no deliberate care. After growth becomes dense, attention should be paid to ventilation and air permeability, otherwise the plant is prone to yellowing.

Hydroponic Centella asiatica

Hydroponic Centella asiatica: Take a section of root with more than 2 nodes and soak it in clean water for 2 days; small rootlets will grow at the nodes of the Centella asiatica, and sometimes small leaves will also grow. Put a small amount of growing soil in a shallow pot, gently place the Centella asiatica roots on the soil surface, cover with a thin layer of soil, then add some small gravel to keep the water clear. Water until the small gravel is submerged; after about 4 days small plantlets will grow. Be careful to replenish water frequently, preferably enough to wet the gravel.

1. There is no need to change the water especially frequently; on the premise of ensuring there is enough water in the basin, changing it once a week is enough. In summer, the water can be changed a bit more frequently, mainly to prevent mosquitoes from laying eggs in it.

2. Maintain sufficient light; only when it receives more than 4 hours of sunlight per day can Centella asiatica grow vigorously and emerald green. Centella asiatica especially likes sunlight; under sufficient sunlight it can grow rapidly even without fertilizer. Conversely, if there is insufficient light or it is placed in a dark room for a long time, the leaves of Centella asiatica are very likely to turn yellow and wither.

3. As for fertilizing, there is no need to be too particular. If you keep goldfish at home, you can pour the water from changing the goldfish water into the water basin of the Centella asiatica, which can make the Centella asiatica grow better.

4. In the south, it can survive naturally very well when growing within the temperature range of 16-24°C. But too high or too low a temperature will inhibit the growth of Centella asiatica, and at high temperatures small insects are also more likely to breed in the water.

5. When growing Centella asiatica in water, yellowed leaves will rot in the water and spoil the water quality, so we should regularly check the water container and promptly remove any moldy or rotten leaves found.

6. Vigorously growing Centella asiatica can spread to fill the water basin in just one month, so we should appropriately prune and divide it, transplanting overly dense Centella asiatica into other water basins, so as to prevent mature leaves from blocking light to young leaves and affecting normal plant growth and metabolism.

The symbolism of Centella asiatica

Centella asiatica has round leaves, like mini lotus leaves, quite cute, and like ancient copper coins, symbolizing reunion and continuous good fortune. Moreover, the name carries the two characters “copper” and “coin”, so its meaning is naturally different: having copper coins at home means rolling in wealth, so it is regarded as a symbol of wealth.

Reasons for yellowing leaves of Centella asiatica

(1) Watering with “half water”, that is, watering is not thorough enough, and no seepage appears at the bottom of the pot.

(2) Being exposed to cold in winter, the root system has already been frostbitten.

(3) After overwintering, being in a hurry to move it outdoors and placing it in a warm place to sunbathe, it temporarily cannot adapt to the sudden climate change.

(4) The potting soil has been too wet or too dry for a long time, and watering has not been done whenever the soil becomes dry.

(5) Being placed for a long time in an environment with poor ventilation conditions.

(6) The leaf surface has not been sprayed and cleaned for a long time, allowing dust to accumulate and hindering photosynthesis.

(7) Lack of potassium; simply add an appropriate amount of plant nutrient solution.

The Feng Shui role of Centella asiatica

According to our understanding of Centella asiatica, we all know that Centella asiatica is not strict about water quality and can be cultivated in low-hardness freshwater. In warm regions it can be potted outdoors, and it is suitable for water trays, aquariums, ponds, and wetlands, and for indoor water landscaping; it can purify water quality, and the green leaves of Centella asiatica can purify indoor air, so it is beneficial to the indoor environment. From this aspect, Centella asiatica can bring good Feng Shui.

Furthermore, according to Chinese culture, which emphasizes symbolism and homophones, Centella asiatica has round leaves, like mini lotus leaves, quite cute, and like ancient copper coins, symbolizing reunion and continuous good fortune. Moreover, the name carries the two characters “copper” and “coin”, so its meaning is naturally different: having copper coins at home means rolling in wealth, so it is regarded as a symbol of wealth. Therefore, from the aspect of symbolism, it also implies good Feng Shui in relation to money.