How to Fertilize Plants in a Terrarium

Plants growing in terrariums usually require less care than other plants. They need less water, and all the humidity they need is supplied by the terrarium ecosystem. They also generally do not need fertilizer. In fact, fertilizer can cause harmful salt buildup in the soil and cause terrarium plants to grow too quickly. However, there are circumstances when you need to fertilize terrarium plants.

Difficulty: Easy

Instructions

1. Watch for signs of nutrient deficiency in the terrarium plants. Nutrient deficiency is the primary reason why you might need to fertilize terrarium plants. Yellowing leaves, spindly growth or no growth at all are signs of nutrient deficiency.

2. Eliminate other possible causes of yellowing leaves and poor growth. Excessive water can cause these symptoms. If there is standing water in the terrarium, let it drain and see if the symptoms go away. Other possible causes include root-eating insects, such as nematodes, and extreme heat.

3. Fertilize with a water-soluble fertilizer the next time you water if you believe your terrarium plants are suffering from nutrient deficiency. Mix about 1/4 of the recommended amount of fertilizer with water.

4. Monitor the terrarium plants for signs of improvement. If the symptoms go away, do not fertilize anymore. If symptoms persist, continue adding the deluded fertilizer mixture once a month.

5. Mist terrarium plants after you fertilize. Because temperatures in terrariums are high, plant foliage is especially susceptible to fertilizer burn. Misting the plants washes away any fertilizer on the foliage.

Tips & Warnings

• If you think extreme heat might be the cause of yellowing leaves or poor growth, place the terrarium away from direct sunlight. Direct sunlight usually causes terrariums to become too hot.
• Do not follow the directions on the fertilizer packaging. Use a diluted solution for fertilizer and do not use the fertilizer every time you water.