Step 1. Step 1. Add soil to the pot until it reaches the same area as before the rot. While this may work, it is best to keep the roots from touching the water. Root rot can occur. While some cactus can be fine for cats, others can cause serious health problems. 1. Before you start digging it up, mark the north end of the cactus using chalk. If that is true of your forest plants, you should follow the exact same instructions as those for indoor plants. Overwatering can pose a serious risk to your succulents, whether they're indoor, outdoor, desert, forest, or both.