The Thanksgiving Cactus and the Cristmas Cactus

In late October and early November the plant growers bring out the Zygocactus (Schlumbergera) group that include both the Christmas and Thanksgiving cacti. These two plants species have flowers that are similar but the stem structure is different on each, although the flower shape and size are the same. Schlumbergera are true cactus and like their relatives, they do not have true leaves. The thick green segments that emerge from the soil are stems that hold water. And like any other succulent, they do not like to be over watered. As the name implies, the Thanksgiving cactus supposedly blooms sooner than its compatriot. After many years of cross breeding these plants, I have not come across many plants that have the old-fashion characteristic structures of the stem segments. Most of the plants grown today have similar shape to the stems.

When you purchase one of these plants, they are usually in bud and bloom, and will flower for four to six weeks if they are in a cool area. As with any plant in flower, the lower the light and the cooler the temperature, the longer the flowers will last and the longer it will continue to bud. Of course, we all would like to have them in full bloom on the holiday they are named after, but sometimes the plants just do not cooperate.

The cycle of these plants begins when you bring them home. If the trip from the grower and then to the retailer was not too stressful, the plant should hold up well and not drop many buds. Remember, taking a tropical plant out into cold temperatures from warm greenhouses is very stressful and can cause all the buds to drop once placed in you home. Put the plant in a plant sleeve or paper bag when the temperatures outside are 50 degrees F. or colder. Plastic can transmit the cold air directly to the leaves much easier than paper because paper is has a much better insulation value because of the air trapped with in.

The plant should have good bright light but little direct sun while in flower. Allow the top 1/3 of the soil to dry between watering. A bit of blooming fertilizer once a week can sometimes prolong the blooming period if the days are bright and the nights are cool. Be sure to remove spent flowers so the new buds have room to open. Remember to allow your plant to spend a week or two adjusting to its new environment before you give it any fertilizer. Too soon and the roots may burn from the salts in the fertilizer when it stays in the soil too long before being absorbed. Just a pinch of a fast releasing fertilizer in a gallon of water is what will aid the plant in producing more buds.

After the all the flowers have gone by and no new buds appear, this marks the end of the flower cycle. At this time the plant should have good light all winter to maintain the top growth. Early morning sun before 11:00 A.M and after 3:00 P.M. in winter is ideal for these plants. And if you live in New England, any sun it can get is best because here we have so little direct sun in winter. Allow the top 1/3 of the soil to dry before watering again. I usually recommend filling the pot to the top rim when watering. Never give the plant so much water that it flows out the bottom. This only leeches all the nutrients from the soil and leaves the plant without any of the things that it needs to build new cells.

In March it is time to transplant your plant into a larger pot. Just remember not to go too big because the plant needs to be pot bound in order to flower. If you over pot and get lucky and do not over water it, flowing may take several years. Just put the plant in the next size pot. Keep the soil evenly moist all summer. After new growth appears, begin a weekly fertilizing program with a weak solution of a high phosphorous fertilizer--a blooming type. Continue until mid to late August and then stop completely.

When the warmer weather approaches and the days get warmer, many plant owners put their plants out side to reap the benefits of the tropical-like environment. If you do decide to put your zygo cactus outside for the summer, please remember to give it full shade all day. The sun can really damage the plant and kill it before it has a chance to acclimate to that amount of sun after bing inside all winter. Also, after bringing the plant back inside for the winter, the lack of light will cause sever stress and literally starve the plant that has been in the full sun all summer.

In the fall, these cacti need to have very cool (just above freezing) temperatures and dark nights to set bud. Since I have radiant heat in my home and there are no really cool spots, I unusually put mine outside in the fall when the temps are in the upper 40s during the day and bring them in at night. Usually just two or three trips outside will cause the plants to set bud. If I can time it right, I sometimes can get lucky and get the little buggers to flower at the holidays. Sometimes! If yours are outside, leave them there until the nights are in the lower 40s but and when you bring them in they will burst into bud.

In the first flowering season when you bring the plant home, I recommended a very weak solution of fertilizer to keep the plant flowering longer. But if you have been diligent with the fertilizer all summer, you will not have to do this now. Just allow the top 1/3 of the soil to dry while in flower and for the remainder of the winter. And the cycle repeats itself.

Unlike most succulents, the zygo group can actually do extremely well in low light. If you can read without eye strain in the existing light, this is low light. Low light is defined as the amount you can read comfortably in daytime without adding any other light source. But these hardy little succulents will grow and thrive in low light if watered correctly. Just remember the less amount of light the plant has, the less amount of water it needs.

I have transplanted hundreds of "Grandma's Christmas cactus" that has been in the same pot for as long as 30 years. That was the longest time a plant remained in the same pot that I had to transplant. These zygos are extremely hardy and can stay in the same pot for many years because they have very thin hair-like roots. However, I do not recommend letting your plant remain pot bound for even a year. It just isn't healthy for it. It is much better to report it every year into just a slightly larger pot. If you put your plant out each summer, you are risking the fast growth of these plants, and too soon they will out grow the available space. Leaving the plant inside all year and putting it outside in the fall to initiate bud, will help keep the plant in a more manageable size for a much longer time.

When a huge plant comes to me for help, one that is put out every summer, fertilized heavily and comes in double the size each fall, it will soon need to be cut back to a more manageable size. I have divided hundreds of huge zygo cactus in the fall because they are just too big to handle. It is easy to do and if the plant is healthy it usually comes out of shock quickly. The best time to do this, however, is spring because the plant may not flower after a root prune. And who wants to miss this amazing display especially if the plant is big and has been give fertilizer all summer?

Insects will infect these succulents from time to time especially if the plants are outside for the summer. Mealy bug is a firm lover of all succulents and the zygo are on the menu. Once an infestation begins in your plant, it can spread quickly into most of the other specimens in your home. I have had the unfortunate problem with mealy bug in my home for many years. Even though I usually do not put my plants outside for the summer, these little beasties have managed to find their way into my domain. I have been dealing with them for many years, and have yet to get rid of them completely. Mites have also infested the stem segments on one of my cactus. I usually do not have problem with mites, but since I was disabled for over a year and not able to take the kind of care needed to keep these things at bay, I have some infestations that now need constant control.

In the pictures I have added to this article, you can see the difference between the one plant (the smaller of the two) that had the infestation of mites. These plants did not have mealy on them, but because I never realized that mites loved zygo cactus, I ignored the problem until it became so obvious that it jumped out at me. I'm surprised the mites didn't get me first!! I then treated the plant and it is beginning to come back. In fact, it actually has one bud on it!

The stem segments on the plant that had mites show the damage the insects cause. They suck the nutrients from the stem segments leaving a motley, spotted appearance to the area (shown in the close-up). Unfortunately, this damage will never go away, but I know the infestation is gone when I see the new growth is coming in all green and healthy. You can easily see the difference between the two plants in size and healthy appearance in the color and firmness of the stem segments. The larger has never had mites and is twice the size as the one that had the infestation even though they are planted in the same size pot. In spring, I will have to do slight root prune to get the plant back into balance again.

There is also one other plant in the pictures that is not a member of the zygo group. Even thought it looks similar, it is a different genus. The third plant in the tall green pot is a Rhipsoalidopsis gaertneri, the Easter Cactus or Spring Cactus. This plant also has stem segments and not true leaves, but the flower structure is very different. (Plants are categorized by the structure of their flowers.) This plant usually flowers in the spring, but it too can be pushed into flower at different times of the year by artificially adjusting the light and temperature that triggers the flower cycle. This plant also had mites and I almost lost it during the time I could not care for my plants properly. I treated it with an insecticide and it is now making a come back, I am happy to say.

With outside perennial beds, the plants only flower once a year, and to have color all season long, you need to choose plants that have different flowering times. The same goes for your interior garden. Most of these tropical plants are perennial and only flower once a year as well, but some like these flowering forest-type cacti, can be nudged into blooming several times throughout the year. In some greenhouses, I often had the zygos blooming with a few buds coming all through the year.

In both these genus of plants, the care requirements are the same but the flower time and structure are completely different. Both are easy to grow and both genus have many cultivates to collect if you can find them. So if you like to have that bit of color amongst your collection, adding some of these easy to care for plants will show their colors to brighten your interior spaces.

If you have questions about your houseplants I will always be happy to help. Please contactme at designer@nature-in-design.com and I will be happy to answer any questions you may have about your plants.