Tuesday, February 12, 2008

Melocactus azureus

Melocactus or Melon Cactus comes from Mexico and Brazil, and there are about 40 species in this genus. This is a finicky genus. Everything needs to be just right--sun exposure, temperature, watering, soil composition, and drainage. Other cacti are more forgiving regarding their care. This genus takes a little more effort. The cactus pictured is M. azureus. This species has a blue-green body, hence the species name.

Melocactus waits until the body finishes growing before it forms a woolly top, or cephalium. Bristles and small red flowers appear from this cephalium, and the cephalium can keep growing for years. Sometimes it will grow taller than the body of the cactus. The average body can grow to about eight inches tall, but I've seen larger ones at cactus shows. Once it forms a cephalium, it should not be repotted. This is a young specimen, so I have quite a few years left to decide what kind of permanent pot it’s going to get. In the meantime, I’ll repot to a larger container every couple of years.

Unlike most cacti, Melocactus needs regular water, even in winter, and should never be allowed to completely dry out. It needs good drainage, and some sources say to use only distilled water. I use filtered water, and so far, so good. Instead of humus rich potting soil, pure quartz gravel can be used instead of soil, but that's not something you can easily find at the local nursery. When the cephalium begins to grow, it resembles a cap, so this cactus genus is also called the Turk’s Cap Cactus.


Teri said...

Hi Aiyana, so that's what the name of this cactus is! Also, I tagged you to write 5 things about yourself. See my blog today. :)

Unknown said...

I think I have this cactus, only its cephalium is made of cathair. (LOL LOL LOL)

Anonymous said...

It's so interesting to read about finicky cacti - I just always thought of cactus as resilient, super low-care plants.

kate said...

Hi Aiyana,

I had one of these and we got along well together. It grew very slowly, but grow it did. Then I lost it when we were hit by a hard frost. Although it was covered, it turned to mush.

How are things going these days?

Mr. McGregor's Daughter said...

I think this is one of the cacti I have. Its needing more water than other cacti may explain why it hasn't been looking so good. (I am a chronic under waterer of houseplants.) Then again, maybe it's something else, as I have managed to keep this plant alive for over 10 years.

Julie said...

This is a cute, finicky boy!!! Reminds me I have a cactus that I see is rotting at the bottom out on my picnic table that is in a shallow dish, with drain holes and cactus soil! Who would think it??? It hardly ever rains here!!! Oh well...yes...even cactus have their parameters to live within. I suppose I am lucky all my other ones have survived over a year already (well, 2 anyway)!!! LOL.

Aiyana said...

Teri, Thanks--I've done this meme before, but if I think of 5 new things, I'll let you know!

Jodi, If people come over and see cat hair, just tell them that's not hair but cephalium. I would bet that not one out a hundred would have any idea what you are talking about! LOL.

nikkipolani, Surprisingly, there are a number of cacti that require specialized care. I like to stick to the easy stuff for the most part. Less expensive that way.

Kate, frost--then mush--the usual outcome! Things are not yet settled re. my husband after his GI bleed, followed by the MI. He has back surgery scheduled next week--risky in his weakened condition, but a must have or he is going to lose use of one leg. He said he'd rather take the risk than become dependent on a walker.

Mr. McGregor's Daughter, If you've kept it alive for 10 years, then don't change a thing!

Julie, you can't win 'em all. I used to agonize over every plant death, but I've mellowed out a bit. Just lost a cactus yesterday to an electrical shearer cord when it got tangled in the cactus. This time, I just said, "sayonara Opuntia subulata," no problem!

Anonymous said...

I love seeing your dry, warm cacti. We just broke a snowfall record - 79 inches and only mid-February. I like snow well enough, but I sure would like to be personally introduced to your desert and cacti right about now.

Yolanda Elizabet Heuzen said...

I had not realised that some cacti are such prima donna's. Last sunday I was at the arboretum Trompenburg where they have quite a collection of cacti as well. Unfortunately I was unable to take pics, sorry!

Weeping Sore said...

Yikes, what an unfriendly looking plant! In my dotage, I've learned that not all succulents are prickly cactus, and I've learned to enjoy cultivating the softer ones. My latest love is kalanchoes that are all turning a glorious red these days.

Anonymous said...

I like to visit you blog because it is so different.
This is a very cool little cactus.
I'm sure I would kill it stone dead.

kate said...

Hi Aiyana,

Thanks for the update. I hope that your husband's surgery goes well - I can certainly understand his reasons for wanting to go through with it. What day is it scheduled for next week? Please let us know how things go!

I came over to say there is a cool photograph on www.kipali.com ... duh, an Echinops, I think. Talk about mush - that seems to be happening to my brain these days!!

Anonymous said...

Thanks so much for stopping by my blog. I can't imagine growing cactus. I may have spot for an indoor cactus at my new house. I do get upset when I lose a plant of any kind. I almost stopped by the road today and picked up some nandina bushes someone had thrown in a trash pile. You blog is very interesting and fun to read. Great info!

P.C.Casey said...


I just bought a Melocactus ferreophilus and I wanted to learn more about its care. I notice that it should be watered regularly. Exactly HOW regularly? Once a week> Twice? I have never owned a cactus, but I have six succulents. I water them pretty regularly, lightly every few days. They are doing great. What about this guy?

Aiyana said...

Hi Peter,
There are so many variables regarding the term "water regularly." It is dependent on the size of the cactus, the type of container, your climate, where you keep the cactus, etc. I would suggest the best bet for you is to invest in a moisture meter from Home Depot or a nursery (cost about $15) and use it to determine how quickly the soil dries. The trick to this cactus is to not let the soil completely dry out, but it should never stand in wet soil. A porous soil mix is a must. If you live in a dry climate like AZ, a light misting several times a week in summer is appreciated by the cactus. This cactus takes more care than many other genera and species because of its different watering needs. It also needs to be watered in winter, but because the soil doesn't dry as fast in winter, fewer waterings are necessary. Hope this helps,