Best Fertilizer for Calathea: Keep Your Indoor Foliage Lush and Vibrant

What Makes Calathea Special?

Calathea is a popular indoor plant known for its colourful, patterned leaves. You might know it as a prayer plant because its leaves move up and down with light changes. Calatheas come from the tropics, which means they like warm air, soft water, and steady feeding. If you want bold, bright leaves, using the best fertilizer for calathea is key.

These plants don’t bloom often indoors, so leaf health is the main goal. Calathea needs nitrogen (N) for leaf growth, phosphorus (P) for roots, and potassium (K) to prevent stress. It also needs calcium and magnesium to stop the edges from browning.

Start feeding once new leaves appear in spring. We recommend CompleteGrow All Purpose Indoor Plant Food. It’s gentle and pH-balanced, making it the best fertilizer for calathea during active growth. Use it once a week, diluted to half strength, and avoid letting the soil dry out completely.

If you’re using tap water, let it sit out overnight before watering. Calatheas are sensitive to salt, chlorine, and fluoride—all of which can cause leaf tip burn. Pairing filtered water with the best fertilizer for calathea helps avoid these issues.

How and When to Fertilize Your Calathea

If you grow calathea in a pot, remember that nutrients wash out faster. You’ll need to fertilize more often than outdoor plants. The best fertilizer for calathea in pots is a complete liquid food with nitrogen, phosphorus, potassium, and trace elements.

Spring and Summer: Feed weekly with CompleteGrow Indoor Plant Food at half strength.
Autumn and Winter: Feed once every 3–4 weeks or when new leaves appear.
Signs of overfeeding: Brown edges, curled leaves, or crusty soil.

Switching between warm and cool indoor temperatures can stress calatheas. Don’t place them near air vents or heaters. Always water before fertilising to avoid root burn.

Using the best fertilizer for calathea along with proper care helps prevent common problems like yellow leaves, faded colours, or stunted growth. If your calathea has dull foliage or grows slowly, it’s likely hungry for nutrients.

Solving Fertilising Issues with Calatheas + FAQs

Fertiliser can help or harm calathea depending on how it’s used. Overfeeding can cause salt build-up, leading to crisp leaf tips or root burn. Underfeeding can result in stunted growth and fading colours. If your calathea is struggling, always check these factors first:

Is your water filtered or chlorine-free?
Are you fertilising with a complete, balanced formula?
Is the soil draining well?
Have you cleaned the leaf surface of dust so it can photosynthesise?

The best fertilizer for calathea will work even better when paired with proper light, humidity (50%+), and regular watering. Keep your plant in bright, indirect light and maintain consistent conditions to avoid shocking its sensitive system.

FAQs: Best Fertilizer for Calathea Plants

Q: What is the best fertilizer for calathea?
We recommend CompleteGrow All Purpose Indoor Plant Food. It’s low-salt, pH balanced, and specially designed for indoor foliage like calathea.

Q: Can calathea be over-fertilised?
Yes. Overfeeding causes brown leaf tips, salt crust on soil, and even root damage. Always dilute your fertiliser and feed less often in winter.

Q: Is organic fertiliser okay for calathea?
Organic options may work, but they’re harder to control indoors. CompleteGrow’s liquid formula is safer and more reliable for indoor settings.

Q: What signs show my calathea is nutrient deficient?
Look for yellowing, small new leaves, pale patterns, or slow growth. These are signs it needs nitrogen, magnesium, or iron.

Q: Can I use the same fertiliser year-round?
Yes. Just adjust the frequency and dilution. Use full-strength in summer and half-strength or less in winter.