What to Do If Sapium Sebiferum Is Slow to Germinate
A brief experience on how to deal with slow germination of Sapium sebiferum, including cause analysis and cultivation methods, is introduced as follows:
Sapium sebiferum, which I believe many of you have seen before, is a colored foliage species similar to red maple or acer palmatum. Its leaves show different colors with the change of seasons. Although the leaves fall in winter, the small white fruits it produces also create a unique scene. This is also the reason why Sapium sebiferum has become increasingly popular in the seedling market and as a landscape species in residential areas in recent years.
Red-leaved Sapium sebiferum
A few days ago, a manager in charge of landscape construction in a residential area called me and said that he had planted four small Sapium sebiferum and one slightly larger one in the community. Four days after planting, all the small ones germinated, but the larger one did not, and its leaves had mostly fallen off. He scraped the bark with a key and found no signs of drought or dehydration in the trunk. I concluded that there was nothing seriously wrong with this tree; it was just slower to germinate compared to the smaller ones. However, one must not be careless in the maintenance of the tree. I then advised my friend to take certain measures to ensure its survival after germination.
Sapium sebiferum with white fruits in winter
As a deep-rooted species, Sapium sebiferum is highly adaptable to soil, can tolerate intermittent or short-term flooding, resist strong winds, and requires sunlight, temperature, and light. Its growth rate is also fast. However, with the continuous changes in climate and frequent extreme weather events in recent years, its growth environment has been affected to varying degrees. Smaller Sapium sebiferum with smaller trunk diameter and crown width may have less nutrient consumption and higher survival rates compared to larger ones, but this is not absolute. With good soil drainage and aeration, Sapium sebiferum of any size can be transplanted and survive. So, what measures can be taken to promote their survival when Sapium sebiferum is slow to germinate?
Recently planted clustering Sapium sebiferum
Reasons for Slow Germination of Recently Transplanted Sapium Sebiferum:
1. Planting too deep or accumulated water at the roots. Although Sapium sebiferum can tolerate intermittent or short-term flooding, it does not mean they can be soaked in water for a long time. If planted too deep or with accumulated water at the roots that cannot be drained in time, it will affect root respiration. Weakened root respiration will affect its subsequent germination.
What to Do If Sapium Sebiferum Is Slow to Germinate
Ungerminated Sapium sebiferum
2. Soil too sticky or the water for setting roots not thoroughly applied. Sapium sebiferum is relatively adaptable to soil compared to other species, mainly in terms of salinity and alkalinity, not soil stickiness. The higher the soil stickiness, the worse the aeration, which naturally affects root development and thus germination. There is also another situation, where the soil is loose and clumpy, which requires continuous watering and tilling. If Sapium sebiferum is planted in this type of soil, watering should be carefully done, as it requires longer watering time than other species. After watering, check the adhesion of the roots to the soil, or it will affect the later germination progress.
Checking if Sapium sebiferum roots have accumulated water and rot
3. Excessive sunlight in the planting area, leading to excessive exposure. Although Sapium sebiferum is a sun-loving species, if planted in an area with long exposure to direct sunlight, it can lead to rapid water evaporation, with old leaves turning yellow and withering, and nutrients in new leaves being lost faster. Insufficient water and nutrient supply will also affect subsequent germination.
4. Insufficient pruning of branches. The best planting time for Sapium sebiferum is generally controlled between the end of March and the beginning of May. After this period, as the temperature continues to rise, the survival rate will decrease significantly. In addition to grasping the planting time, it is more important to strengthen the pruning of its branches. If we retain too many branches during this season, although it may look good temporarily, it will increase nutrient loss and affect subsequent germination.
Reasonable pruning of Sapium sebiferum
Measures to Promote Germination After Transplanting Sapium Sebiferum:
1. Place perforated ventilation pipes on both sides of the soil ball. When planting Sapium sebiferum, we can place two sections of 80cm long, 110mm diameter perforated PVC pipes (with holes around the tube wall) on both sides of the soil ball. This can ensure root aeration and check for积水, ensuring proper root respiration and drainage. The planting depth should not be too low; Sapium sebiferum should be planted slightly higher, with some ceramic balls or lightweight rocks placed at the bottom of the soil to reduce the probability of积水 and root rot.