Unlike plants growing in the ground, potted plants can't seek their nutrient elsewhere except the limited media they are provided. Houseplants are usually slower growing and more resilient so a lot of time the deficiency in the potting soil isn't noticable for a long time. Thus it is very important to check if the houseplants are growing as they
should given the right conditions. Here are my recent experiences with some poor quality mix and how they affected the plants.
I used to buy potting mix at the store for houseplants without any problem. Things were different last year and two out of three bagged potting mix were tainted and my dicotyledon plants showed abnormal growth in it. Reluctant to throw 3 cubic ft of mix away, I used the rest for repotting monocots, as they were supposed not to be as sensitive. Most of them did well but certain species stopped growing or even died away. After the big parlor palm died I uprooted it and was surprised to see no
root growing into the new mix underneath. My snake plants survived but again no sign of new root growth, and hence no top growth. I washed out the
roots and replanted in the mix with home made
compost. New leaves are visibly growing a week or two later, gaining 1cm every three days, that's quite speedy for a slow grower like snake plant. So was a golden pothos, I had never seen a pothos that wouldn't grow. Now it is a happy vine after changing the soil.
Another example is a store bought lime tree. I had no idea what was wrong with the potting material that looked like composted barks. But after no growth for two months despite lots of liquid fertilizer and sunlight, I repotted this too. New leaves started to sprout from the tip of every branch and the new leaves are several times bigger. Worrying about excess nitrogen, I looked up
online and found out that was the normal leaf size for a lime tree and all the old leaves were somehow stunted. It was unbelievable a tree coming from a nursery was so unhealthy to begin with.
Now I am a bit paranoid about outside resource and start switching to home made potting soil. If you have plants that are not growing it may not be your fault, try changing the soil and it might work out magically.
2
