The orchid is a popular flowering houseplant, but its care is often confusing, especially regarding watering. Unlike most potted plants, common household orchids are epiphytes, meaning they naturally grow on trees or rocks with roots exposed to the air. This unique growth habit makes the traditional watering can method inappropriate. Soaking is the most effective way to hydrate them, and understanding the proper frequency and technique is key to ensuring your orchid thrives.
Establishing the Baseline Soaking Frequency
For common indoor varieties, such as the Phalaenopsis (Moth Orchid) and Cattleya, a starting point for soaking frequency is every seven to ten days. This rule applies when the orchid is potted in a coarse, bark-based growing medium, which is designed to dry out rapidly. The goal is to allow the roots and the medium to dry almost completely between waterings, preventing the root rot caused by suffocation.
This interval is heavily influenced by the immediate environment and changes throughout the year. For example, an orchid in a warm, bright location may require soaking at the seven-day mark. Conversely, one in a cooler, dimmer spot may easily wait ten days or more.
Proper Soaking Technique
Soaking ensures the water-absorbing root tissue, called the velamen, is fully rehydrated. To begin, remove the orchid from its decorative cachepot and place the inner growing pot into a sink or a bowl. Use lukewarm or room temperature water, as cold water can shock the root system.
Fill the container until the water reaches about halfway up the pot, or completely submerge it. Allow the orchid to soak for 10 to 20 minutes, giving the medium and roots ample time to absorb moisture. After soaking, allow the pot to drain completely for 10 to 15 minutes. Never let the orchid sit in a decorative pot containing standing water, as this prevents air circulation and promotes root rot.
Environmental Factors That Adjust Watering Frequency
Ambient conditions significantly determine soaking frequency. Warmer temperatures increase the rate of water evaporation from the potting medium, meaning the orchid will dry out faster and require more frequent soaking. Conversely, cooler environments or winter months slow the evaporation rate, requiring a reduction in frequency.
Humidity is another major variable, as orchids prefer 50 to 70 percent humidity. In homes with dry air, the medium will dehydrate more rapidly, necessitating shorter intervals between soaks. The type of potting medium is also influential; while bark chips support the weekly baseline, sphagnum moss retains moisture much longer. An orchid planted in sphagnum moss may only need soaking every two weeks.
Visual Cues Your Orchid Needs Water
The best method for determining when to soak is by observing the orchid itself. The most reliable indicator is the color of the roots, which are often visible through clear plastic pots. When fully hydrated, the roots appear plump and bright green.
As the plant dries out, healthy roots change color, turning a silvery-gray or whitish hue. This silvery appearance signals that the velamen is dry and ready to absorb water. Another practical check is lifting the pot; a surprisingly light pot indicates that the moisture has evaporated and a soak is due. A severely dehydrated orchid may also show slight wrinkling or a leathery texture on its leaves.