What to do about rotten leaves and dry edges on crown of thorns (Euphorbia milii) in winter?

Crown of thorns (Euphorbia milii) is a flowering plant that many gardeners like to grow, and because of its high ornamental value, it is being used more and more widely. But for home growers, it is generally grown as a potted plant for appreciation. What matters is that crown of thorns not only blooms beautifully, but its flowering period is also especially long, and with good care it can even be expected to bloom in all four seasons.

But after winter arrives, the crown of thorns grown by some gardeners may develop poor growth such as rotten leaves and dry edges. This will inevitably greatly reduce the ornamental value of the potted crown of thorns, and of course this is also a phenomenon we are very unwilling to see.

First we need to check the ambient temperature to see whether the plant has been frosted, because crown of thorns has relatively poor cold tolerance and is prone to cold damage when the temperature is too low. If it has been frosted, take warming measures in time; if it has not been frosted, the rotten leaves still need to be cleaned up in time to avoid breeding harmful bacteria.

But crown of thorns is a plant whose branches are covered with sharp spines, so when cleaning up rotten leaves you must be careful to avoid being pricked. Its sap is also toxic and can easily harm the human body. If during the cleanup of rotten leaves you find branches damaged by cold, they also need to be cut off in time.

In short, whether rotten leaves or rotten branches, they must be cleaned up in time to avoid infection after rotting that damages the plant's growth. And after pruning, the wounds also need to be treated; you can sprinkle some carbendazim powder on the wounds, or apply some plant ash to inhibit bacterial invasion.

In addition, after pruning is finished, we also need to observe the dryness and moisture of the potting soil. Crown of thorns relatively prefers a slightly drier potting soil environment and is afraid of waterlogging, especially in winter. So when watering, you must wait until the potting soil is very dry before watering. For winter care, try to achieve preferring dryness over moisture, otherwise if the humidity is too high it can easily cause stem rot.

If you want to repot, it is recommended to wait until next spring when the temperature reaches above 15°c. When repotting, remove the outer old soil and replant using new potting soil with high looseness and strong air and water permeability. And after repotting, do not rush to water, because it is itself relatively drought-tolerant, and just after repotting it has not yet fully settled in, so when the potting soil is not very dry, do not rashly water.