Christmas Cactus Watering Guide: How Often To Water Plants For Better Blooms

Holiday cacti are wonderful winter-flowering plants that are easy to care for, but Christmas cactus watering has to be done correctly for optimal health and seasonal blooms. New owners may wonder how often to water Christmas cactus plants. The answer will vary by the plant's size, location, ambient moisture levels, and soil type. These cacti aren’t desert specimens and have specialized watering needs to keep them happy and blooming.

Regular watering is a crucial aspect of Christmas cactus care. As with other types of holiday cactus, the right moisture balance is key to making a Christmas cactus bloom. If you aren't sure whether you have a Christmas cactus, Thanksgiving cactus, or Easter cactus, then you'll be relieved to know that their watering requirements are very similar.

In their native tropical rainforests of Brazil, Christmas cacti are epiphyte plants that grow in the crotches of trees or rocky crevasses. They receive their moisture from the humid air, rainfall, and morning dew dripping down from the tree canopy. In this way they are very different from their desert cacti cousins, who have a high drought tolerance and can go long periods without water.

How Often to Water Christmas Cactus Plants

How often to water a Christmas cactus is a common question. These plants prefer fairly high humidity and moist, although not soggy soil. The ideal Christmas cactus soil mix should be fairly peaty with vermiculite or perlite to help hold moisture.

In the winter the plant needs water every three or four weeks. But during the blooming period, it requires more frequent moisture and soil should not be allowed to dry out to encourage prolonged flowering. During the growing seasons of spring and summer, water the plant on average every two weeks.

This schedule is subject to soil type, where the plant is growing, and other factors. For example, if the plant is in garden soil, it will dry out more quickly and need more frequent watering. If the cactus is near a drying heating vent, it will also need to be irrigated more often.

While guidelines on how often to water a Christmas cactus are helpful, the best gauge is to use your finger to detect when the soil is dry a couple of inches (5cm) down into the soil.

How to Water a Christmas Cactus

While these plants like moderately moist soil, they cannot tolerate being waterlogged. Move the container to the tub or sink when you water. Remove the saucer and let all the excess water percolate through the drainage holes. It is good to soak the soil to let it evacuate excess salts that build up from fertilizing.

Alternatively, you can put the plant in the shower every month and add enough water to the soil surface that it percolates out in a plentiful supply.

Many municipal tap water supplies have chemicals and minerals that the plant cannot tolerate. They are sensitive to chlorine and lime which are often in our tap water. Rainwater, distilled, or filtered water are ideal. You may also opt to let the tap water sit out overnight to off-gas.

From late winter to late summer, feed plants monthly during regular watering. The ideal Christmas cactus fertilizer is a bloom formula houseplant feed or a half-strength water-soluble formula, such as 20-20-20 or 20-10-20.

How Much Water Does a Christmas Cactus Need?

The answer depends on how large the plant is and the container size. Larger plants will need much more water than young, small cacti. In large containers, they will need more than beginner nursery pots. The touch test is the most reliable gauge of whether the plant needs watering.

Overall, water until the moisture is leaching heavily from the drainage holes, then allow it to drain through. This will ensure the plant is not in soggy soil and will also help clean the soil of built-up salts.

When to Stop Watering Christmas Cactus

This plant likes to be evenly moist at all times. It should not be allowed to dry out completely. In the winter, after blooming, Christmas cactus plants will need much less water but they should still be irrigated every three or four weeks. During the growing season, they will need much more water.

If the plant is brought outdoors for the summer, winds and sun will dry out the container much more quickly. Such plants will need watering at least twice as much as plants housed indoors.

How to Spot and Avoid Over or Underwatering

An underwatered Christmas cactus will have dry soil to the touch even at the drainage holes. Look out for Christmas cactus wilting, shriveled and puckered leaves, and wrinkled stem segments. Plant parts can start falling off in extreme cases. Increase watering frequency and use the finger test daily to ensure the soil doesn't dry out too much.

If your plant is drying out too quickly, then learn how to repot a Christmas cactus and move it up a container size. Christmas cacti like to be a bit potbound but should be repotted every two to three years.

Watch out for Christmas cactus diseases in overwatered plants. Signs include soft stems, yellow leaves, and leaf drop. In the worst cases, the plant will rot at the soil line and roots could develop fungal disease. Christmas cactus root rot can quickly be fatal, so if you see any putrid, discolored, or otherwise damaged roots, prune them out with sanitized shears.

Overwatered Christmas cactus care often includes repotting. Before you repot, sanitize the container with 1 part bleach to 9 parts water. Use pasteurized soil if possible to avoid introducing pathogens that will thrive in moist soil.

Should I Mist My Christmas Cactus​?

Christmas cactus is a tropical plant that naturally grows in a humid environment – 50-60% is ideal. Occasional misting won't do any harm but has little effect on raising humidity for houseplants. Instead, invest in a houseplant humidifier or place a tray of pebbles filled with water beneath the container.

Plants also like warmth. The ideal nighttime Christmas cactus temperature is 60-65°F (15-18°C) with a cooler period of about 50°F (10°C) in October to encourage blooms in time for the holidays. Average room temperatures during the day will enable plants to thrive.

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