A general lightening in color of the foliage and production of a smaller sized leaf may indicate that you need to start a feeding program. There are several ways to fertilize indoor plants. Slow release fertilizers are easy to use - you can buy tablets or small granules to spread on the soil surface. Follow the manufacturer's directions. These fertilizers generally last three to four months.
Liquid fertilizers are a second.
The manufacturer may recommend the application of a small amount with each watering or larger amounts or longer watering intervals. Feed indoor green plants regularly when they are actively growing. This generally coincides with late spring, summer and early fall months. Apply fertilizers when the soil is moderately moist. You can easily injure the root system if you fertilize an overly dry soil ball.