How to Make a Star Cactus Bloom

Purchase or replant a star cactus that is at least 1 inch in diameter; flowers will not be supported, even in the wild, if the plant base is smaller. Make sure the plant looks healthy and does not exhibit signs of stress, disease, rotting or pests.

Plant the star cactus in a porous, alkaline soil -- not sand -- in the shallow potting dish with holes in the bottom for additional drainage. Commercial soils designed specifically for succulents can be purchased at a home improvement or gardening store.

Mix 9 drops of white vinegar into 1 quart of tap water in a glass or plastic container; shake or mix well.

Add a small amount of the vinegar-water mix to the dish around the perimeter of the plant's roots, rather than directly on the plant. Moisten the soil but do not allow the cactus to sit in any type of standing water. Terra cotta absorbs water more quickly than do other types of glazed pots, which can assist in keeping the soil moderated.

Place the dish in a sunny location, such as a south-facing windowsill.

Water the cactus again when the top inch of soil is completely dry. If the cactus appears stressed between waterings -- exhibiting wrinkled skin, for instance -- apply a light mist of water with a fine spray bottle.

Place the cactus in a shady, cool place -- such as a closet or garage -- once it has established itself in the new pot and surroundings. The temperature should remain at 45 to 55 degrees Fahrenheit, and sunlight should be limited but not cut off completely. Water only twice a month, and leave the plant in this darker space for one to two months. This may trick the plant into believing it is winter.

Remove the cactus from the closet or garage and place it back on the sunny windowsill. Moisten the soil and continue to water, allowing the soil to just slightly dry out between waterings. Water will promote a period of more-rapid growth.

Apply a cactus-specific fertilizer to the pot once flower blooms have appeared to provide nutrients for the growing plant.