By Erin Marissa Russell
Cacti and succulents differ from other garden plants in that, as native desert inhabitants, they need far less water from the gardener. Although this feature is often touted as making cacti and succulents easier to care for, when you’re used to cultivating plants that need a certain amount of water from you, it can be difficult to change gears and give a plant substantially less hydration. It’s often said that cacti and succulents flourish when they’re neglected, which can be a difficult behavior to transition into for a gardener who’s used to carefully babying their plants. Keep reading to learn exactly how to water your cacti and succulents so they can grow healthy and strong.
When and How Much to Water Cacti and Succulents
One factor when it comes to watering your cacti and succulents that it’s all too easy to forget about is the time of year. These plants need more water when they’re in their active growth period, from March to September, and they need far less water during the rest of the year while they’re in their dormancy.
The hydration needs of cacti and succulents increase along with the amount of sunlight they receive as days grow longer. From March to September, the general rule of thumb is to water cacti and succulents once per week. (This is the time of year when they need fertilizer from you as well.) Give the plants plenty of water when you water them, then allow the water to be absorbed until the top layer of the soil is dry to the touch before your next watering session.
A good rule of thumb to help you water your plants deeply enough is to keep giving them moisture until it drips from the drainage holes of the container. From October to February when plants are dormant, you should only provide them with water if the soil where they’re growing is completely parched.
In the winter, most cacti and succulents only need to be watered about once per month. In springtime and fall, give them the standard once a week dose of water. When temperatures soar and the weather is especially dry in summer, you may need to water them two or three times per week.
However, remember to take rainfall into account for cacti and succulents that are growing outdoors. Also, do a bit of research and know the particulars of the variety of cactus or succulent you’re growing, as there are a few types that do their growing in the winter and are dormant when the weather gets hot.
Intuitively, it would seem that larger plants will need more water, but in fact the opposite is true. Smaller cacti and succulents are producing lots more new cells, and they need plenty of water to fuel that new growth. Another factor that reduces larger cacti and succulents’ need for water is that the ratio between their surface area and their volume is lower, so water doesn’t evaporate from them at the same rate it does from smaller plants. These factors together mean that you’ll need to water smaller, younger cacti and succulents more frequently than you will larger specimens.
Know the Signs of Overwatering and Underwatering
One way to ensure the amount of water you’re giving your cacti and succulents is neither too much or too little but just right is to familiarize yourself with the ways plants will show they are getting too much or too little water. If you see the symptoms below on your cacti or succulents, you’ll know that you need to adjust your watering routine.
- Overwatering: Giving these desert plants too much water is a much more frequent mistake than giving them too little. Cacti and succulents that have been overwatered may show it through the following symptoms: fat leaves or plump appearance, and soggy texture of foliage.
If you notice that one of your plants has been overwatered and the soil is still damp, it’s time to go into rescue mode. Gently remove the plant from the container, and use your fingers to break up and shake off excess soil surrounding the roots. Get the roots as bare as you can without damaging them, then leave the plant to dry out on newspapers in its usual environment for a few days. Use a twig or toothpick to clear any soil clods that may be blocking the container’s drainage holes.
After your cactus or succulent has had some time to lose the excess moisture, replace the soil in your plant’s container, and repot it. Withhold water for at least a week afterward, and adjust your watering amount or frequency to avoid recreating the conditions that led to excess dampness. You may wish to add some sand, fine gravel, or perlite to the potting medium when you replace the soil for your plant to help increase drainage in the container.
- Underwatering: Although it’s true that cacti and succulents don’t need as much water as other types of plants, they do still need a bit of hydration from you. Here’s how you’ll know if your cacti and succulents need a bit more moisture than they’re getting: yellowed, pale, or gray discoloration; distorted leaves; stunted growth; and drooping, wrinkled, or indented appearance.
Stretching upward and becoming spindly or “leggy” may either indicate a need for water or be a sign that the plant is reaching toward the sun due to lack of sufficient light. If you notice a plant wilting, you should take action and water it immediately unless the soil is already moist.
More Tips for Watering Cacti and Succulents
- Growing these plants in the appropriate medium goes a long way toward making sure they don’t get too much water. Cacti and succulents also especially need a soil that provides easy drainage, so water doesn’t sit stagnant around their roots. A substantial portion of your potting medium for cacti and succulents should consist of sand and pebbles so that there are plenty of nooks, crannies, and pores for moisture to escape through. However, the soil should also have some organic material in it, which holds a bit of moisture for the cacti and succulents to absorb through their roots but will still dry out quickly.
- If you aren’t sure whether the soil you’re growing your cacti and succulents in is draining appropriately, you can check it by removing the top layers of soil so you can feel how moist the lower layers are. You can also check how damp the soil is by inserting your finger into the ground near where your plants are growing down to the second joint. If earth clings to your skin or you can feel that the soil is still moist, you don’t need to water your cacti or succulents just yet.
- This next tip applies just as much to the rest of the plants in your garden as it does to cacti and succulents. Containers you grow plants in should come equipped with drainage holes to let excess moisture drip out.
- Different containers will also affect the watering needs of the plants inside. Some materials tend to be more porous and soak up more water. The size and shape also makes a difference, as smaller and shallower containers lose their moisture more quickly to evaporation than larger, deeper pots.
- Cacti or succulent plants that stay outdoors over the winter should not be given any water. Short periods of cold weather are not dangerous for the plants, but moisture and cold weather combined can be fatal.
- Aim the water you give your cacti and succulent plants at their base, above where the root zone lies. Moisture that remains on the foliage of cacti and succulents cannot be absorbed, and it can either cause sunscald when heated by the sun or contribute to excessively damp conditions that lead to disease. Succulents in particular will suffer from disintegration of their tissues where water remains, so blot any moisture that splashes onto their leaves with a paper towel to soak it up.
- Cacti and succulents that you’re raising indoors will always need less water than a similar specimen would if it were grown outdoors.
- Give cacti that are growing outdoors their moisture in the mornings. Watering a cactus plant later in the day can result in the water heating up before it’s absorbed, which can shock the plant or burn its tissues with sunscald. Succulents, on the other hand, should be watered at night, because after dark is when the respiratory process kicks in, so water can be more easily absorbed at this time.
- Do not hydrate cacti, succulents, or any other plants with water that passes through a softening system that relies on salt as its recharging agent. The sodium in the resulting water will be harmful to your plants.
- If you use tap water that is alkaline or hard, containing a significant amount of dissolved minerals, you’ll need to make sure to repot your plants with new soil on a regular basis, as the minerals will accumulate in the soil and eventually reach harmful levels. On certain container materials (especially unglazed clay), these accumulated minerals will gather into deposits that can be unsightly.
- When there’s available rainfall, the best way to give all of your plants the moisture they need is to collect rainwater and use that to hydrate them. During mosquito season, make sure to use water as soon as possible after it’s collected to prevent the bugs from breeding in the standing rainwater. You can also purchase an agitator designed to keep the water moving, preventing the bugs from using your rain-collecting setup as a nursery to make more baby mosquitoes. You may wish to use containers that can be sealed and stored so you can stockpile rainwater when it’s plentiful and use it later in the year when precipitation is less prevalent.
- If you’re still having trouble with getting the right amount of water to your cacti and succulent plants, consider using a moisture meter. Simply press the meter into the soil about three quarters of the way deep, being careful not to disturb the plant’s roots. A few minutes later, the meter will be ready to be read.
As you can see, it’s not quite as simple to keep cacti and succulents hydrated properly as it may seem. There’s a lot to take into account, from the time of year to the type of container. However, after reviewing the tips we’ve presented here, you’re armed with the knowledge you need to give your plants the right amount of water no matter what, so they can keep on growing for years to come.