We’ve all been there. Someone gave us a beautiful cactus, thinking it would be a nice, easy plant for us to take care of and display in our home. It seemed like a simple-enough plant to keep alive, because you don’t have to water it much. . . but somehow you killed it.

I have a confession to make. While working in a greenhouse as a wee little freshman, I was given a cactus. I loved this cactus and did everything I could to keep it alive. I watered it infrequently, kept it in sunlight, and I even took it on an eight-hour car trip. I was dismayed to look in the backseat at the end of the drive and discover that my limp, underwatered cactus had de-rooted and popped out of its pot completely. Turns out, the one thing I hadn’t done was any research.

Perhaps there’s more to keeping a cactus alive and in good health than many of us think there is. Want to learn how to care for your cactus? Well, now I’ve done some research and am here to help!

All cacti belong to one huge family of 1,866 species that are categorized into 131 genera. According to the Guide to the Vascular Plants of Tennessee (edited by the Tennessee Flora Committee in 2015), the global Cactaceae family is characterized by “mat-forming shrubs,” spines and yellow, “showy” flowers. Most species have no leaves. They can be found in much of North and South America, but Mexico has the most native species of cacti. In the U.S., they can be found in southwestern states. Alaska and regions near Antarctica also have some native cactus species.

You probably already know that in the desert, cacti have amazing heat and drought tolerance. They can survive soil temperatures of up to 158 degrees Fahrenheit. However, different cactus genera have different needs when it comes to water, sunlight and adapting in your home. That is important to remember in the race to saving your cactus or the marathon of keeping it in good health.

There are two basic habitats when it comes to cacti: desert and forest. Your cactus will have different needs based on which one it came from. However, most cactus plants you can find at the store or nursery are not labelled according to genus or habitat. So, the first step to foster your cactus’ best life is to determine whether it is a desert cactus or a forest cactus. This link will help you determine what genus your cactus belongs to and, at the same time, whether that genus is from a desert or forest ecosystem. Generally, a desert cactus typically has many spines and gorgeous flowers. A forest cactus is usually spineless, with oblong stems and beautiful flowers. The Christmas cactus is a forest-native cactus.

Watering a desert cactus is tricky. You can’t water your cactus in a consistent way all year. The way you water will depend on the season, and I think this is where most people mess up. You want to mimic what life would be like on the desert floor. You can water too little, but you can also water too much. The golden rule is to never water your desert cactus so much that it is standing in water, because this will cause root rot. In the winter your plant will be dormant, and it will need to completely dry out before being watered each time. During the rest of the year, it is safe to allow for the soil to become a little dry before watering.

The fundamental rule here is to pay attention to the soil in the pot – don’t just stick to a watering schedule. Your plant is telling you when it’s thirsty; all you have to do is stick your finger in the soil to listen!

A desert cactus also needs strong, direct sunlight cast on its spiny stems. Try to put yours near a window that will receive the afternoon sun. Fertilization can also help your desert cactus to be at its best during the active months from June to September, and a 5-10-5 (5 parts nitrogen, 10 parts phosphorus, and 5 parts potassium) fertilizer will do the trick. Your friendly neighborhood nursery or garden center can help guide you in this process.

Now, on to our forest-loving friends. They do well with considerably more water than desert cacti, so this is where knowing what kind of cactus you have is very helpful. You don’t want your forest cactus to drown, but you don’t want the soil to get completely dry between watering – only slightly. Again, check the soil daily with your finger to determine if it is time to water. Additional instructions for watering to achieve the best flowers possible can be found here.

Indirect sunlight is best, as direct sunlight will burn the cactus’ precious stems. During spring and summer, fertilizing your forest cactus can help it feel at home in your house. Use a fertilizer that has equal parts nitrogen, phosphorus and potassium. The ratio of nitrogen to phosphorus to potassium will be listed on the back of each fertilizer found at your local garden center.

So, there you have it! My guide to watering your store-bought, indoor cactus. I wish you all the best in keeping your beloved gift or self-purchase alive and beautiful. And don’t forget to give your cool cactus a fun name! It adds personality.

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