How to Prune & Care for Orchids

Grow orchids in potting soil made of fir tree bark, tree fern, perlite, charcoal or cork. These match or mimic the tree material to which they attach themselves in the wild. Choose plastic pots to maximize humidity, which tropical orchids need.

Place orchids in a south- or east-facing window, where they will receive lots of bright light, but little or no direct sunlight. Select a bathroom window if possible, as this provides them with much-needed humidity. Shield them from sunburn with a sheer curtain if midday sun hits them.

Keep orchids at room temperature during the day, usually between 65 and 80 degrees F. At night, let temperatures drop about 10 degrees F to promote flowering. Maintain a humidity level of 40 to 70 percent using a humidifier, or place orchids on a tray filled with watered gravel.

Water orchids when the soil dries out, which typically occurs about once a week. Water more during growth spurts and blooming periods and less during dormant periods. Let the water run out the bottom to avoid water-logging, as orchids prefer dry soil. Most orchids store moisture in their leaves, making them relatively drought-tolerant. The main exception is the phalaenopsis orchid, which cannot store water and needs watering before the soil dries out completely.

Fertilize orchids while they are growing with dilute, water-soluble fertilizer. An equal ratio -- such as 20-20-20 -- is ideal for most orchids planted in materials other than tree bark. Those planted in tree bark need extra nitrogen, such as a 30-10-10 fertilizer. Stop fertilizing when they go into a dormant period.

Prune dead roots only if the orchids outgrow their pots and need repotting. Orchids typically don't need pruning, but if you want to trim away dead leaves, wait until after the blooming period.