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Caring for Houseplants

Fertilizing Houseplants

Take care not to over-fertilize your plants. Plants should be fertilized only when they are actively growing.

Most houseplants will not need to be fertilized more than once every 1 – 3 months, between March and September. During the short days of winter, plants experience a rest period and usually need very little or no additional fertilizer. This schedule is sufficient to maintain their health.

If you fertilize more frequently, the plants may outgrow their pots and space too soon. Also, plants may be damaged with too much fertilizer, especially when their growth rate is slowed in dim light. Too much fertilizer can burn roots.

Which Fertilizer?

We recommend a commercially available fertilizer. Specially labeled fertilizers for houseplants work well. A good ratio to choose is a 1:2:1, such as 5-10-5 or 10-20-10. Also a balanced ratio is good, such as 10-10-10. Follow the directions on the label. Never use a stronger mixture than what is recommended.

Fertilizers may be liquid, powder or tablet. Also, slow-release forms can be mixed into the potting soil at planting time or applied to the surface. Most last 3-4 months.

To help avoid a salt buildup in the soil, leach the pot every 4-6 months. Pour a large volume of plain water into the pot and allow it to drain through completely. Empty the saucer.

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