Inspection
It is important to inspect your plants regularly. This is the only way that you can figure out what they need.
Clean
Dust and clean your plants because dirty leaves will impact their ability to take in sunlight. If plants can’t get the light they require, they can’t photosynthesis. A simple wipe down with a wet cloth works great, and gives you the chance to look them over.
Inspect
Make sure you look for dead and dying leaves and prune appropriately. Look for signs of bugs and disease. This is also a good chance to look for signs that your plant is getting the right amount of light and water.
Pests and disease
Pests and disease are annoying and there’s no rhyme or reason why pests or diseases happen. Address the issue before it gets out of hand. It’s always a good idea to have a reliable insect killer/preventer on hand. Natural products like Neem oil work great. Make sure that your product is not too harsh for your plants.
When you see something fishy or questionable, quarantine and move your plant far away from the healthy ones. Unfortunately, pests and disease spread.