Mammillaria Gracilis Fragilis “Thimble Cactus” Care & Buying Guide

Mammillaria Gracilis Fragilis


Light requirementsHigh
Water requirementsLow
Ease of careEasy
Zone9b to 10b
Temperature resistanceNot cold-hardy
Growth speedFast
Indoor growingSuitable


Taking Care Of Mammillaria Gracilis Fragilis “Thimble Cactus”

Ideal conditions

Mammillaria Gracilis Fragilis “Thimble Cactus” is a cactus that loves bright light (shaded to full sun), requires little water, and thrives in warmer temperatures. This cactus may tolerate short-term exposure to low temperatures, but it shouldn’t be kept in temperatures below 25-30 degrees Fahrenheit (-3.9 to -1.1 degrees Celsius).


The water needs of the Thimble Cactus are identical to those of many other succulents. This plant is drought-resistant and should be watered only when its soil is dry to the touch.

Avoid overwatering the Thimble Cactus since standing water is very likely to lead to root rot.

In winter, the cactus should be provided with little to no water. During the colder seasons, the Thimble Cactus is dormant and thus needs very little water to survive. You may not water it at all, or you may occasionally mist it if you are worried.

Take special care not to overwater the cactus in the winter since it’s much more prone to root rot in winter than summer.

Where to plant

The Thimble Cactus should be planted in a light, well-draining cactus mix. You may also add mineral grit like perlite or pumice to enhance the draining ability of the soil.

Requiring shaded to full sun, the Thimble Cactus is best to be kept outdoors. If the winters in your area get cold, then plant the cactus in a pot. Once cold temps settle in your area, you should bring the cactus indoors, which is easy to do with a potted plant.

You may keep the Thimble Cactus indoors as well, but only if you can provide it with at least 6 hours of sunlight every day. If there are no areas in your home that get sunlight most of the day, don’t keep the Thimble Cactus indoors.

Also, even though the Thimble Cactus tolerates extreme heat well, you may want to move it to a shaded location on very hot days.

General care information

Once every year, you should fertilize your Thimble Cactus with a water-soluble fertilizer diluted to half strength. Usually, fertilization of this cactus is done in mid-spring. You shouldn’t need to fertilize the Thimble Cactus more often than once since it’s a small plant.

Aside from fertilization, you may need to think about repotting this cactus at some point. It’s small but fast-growing, so it’s likely that you will have to replace its original pot.

Repotting is usually done no sooner than when the plant comes out of hibernation in spring. Though you may not need to repot the Thimble Cactus more often than once every 2-3 years, you might want to do it every spring. This will allow you to check the condition of the plant’s roots. Some people also believe that introducing the cactus to new soil can boost its growth.