High-K fertilizer for cacti?
- Steve Johnson
- Posts: 4526
- Joined: Thu Nov 03, 2011 4:44 am
- Location: Los Angeles, CA (Zone 10b)
High-K fertilizer for cacti?
I'm sitting on my hands as I wait for the new growing season, so I wanted to prepare some notes. Based on research I looked up at Cactuspedia, I have a few cacti which indicate the need for a high-potassium fertilizer when they get fed over the summer. They are as follows: Eriosyce senilis, Gymnocalycium ochoterenae ssp. vatteri, and Mammilaria microcarpus. Unfortunately Cactuspedia didn't have cultivation pages on those specific species of Gymno and Mamm, so I had to guess by what I thought might be similar enough with other species for their feeding habits.
Assuming that Cactuspedia is reliable, I can say for sure about E. senilis. How about the Gymno and Mamm species I have? Also, what would be a good recommendation for an appropriate high-potassium fertilizer? I'll be using the MSU orchid fertilizer, but I didn't know if it would fill the bill for cacti that need a high-K feeding.
Thanks for any help on this!
Steve
Assuming that Cactuspedia is reliable, I can say for sure about E. senilis. How about the Gymno and Mamm species I have? Also, what would be a good recommendation for an appropriate high-potassium fertilizer? I'll be using the MSU orchid fertilizer, but I didn't know if it would fill the bill for cacti that need a high-K feeding.
Thanks for any help on this!
Steve
- Steve Johnson
- Posts: 4526
- Joined: Thu Nov 03, 2011 4:44 am
- Location: Los Angeles, CA (Zone 10b)
Same here. With that said, I've barely started relearning what I used to know about cactus taxonomy, so I have to rely on the tags that come with the plants I buy at the California Cactus Center. A couple of boo-boos I found were obvious -- for example the CCC tags matanzus as Matucana, when it's clearly Melocactus. That one mystifies me. Other boo-boos aren't so obvious, although maybe I don't have enough brain cells to figure out the taxonomical confusion anymore.luddhus wrote:Gymnocalycium ochoterenae is listed in all important cactus books I have, and on the species list on this site as well.
Getting back to the matter at hand, I realize that a lot of info on the internet is bullplop. Is it indeed correct that Cactuspedia was misinformed about certain cacti needing a particular "high potassium" fertilizer?
Depends on why they wrote it. Did they quote a source? (I have not yet found this "information" on Cactuspedia, so I cannot check.)Steve Johnson wrote:Is it indeed correct that Cactuspedia was misinformed about certain cacti needing a particular "high potassium" fertilizer?
I have never heard of cacti that need more potassium than other species.
Besides, it is "matanzanus".
- Steve Johnson
- Posts: 4526
- Joined: Thu Nov 03, 2011 4:44 am
- Location: Los Angeles, CA (Zone 10b)
Cactuspedia doesn't quote any sources, so the online community there is something I realize has to be taken with more than a few grains of salt. Wish I had more time to search out reliable authorities, but there you go.luddhus wrote:Depends on why they wrote it. Did they quote a source? (I have not yet found this "information" on Cactuspedia, so I cannot check.)
I have never heard of cacti that need more potassium than other species.
Besides, it is "matanzanus".
By the way, I may have misunderstood what I was trying to say. The plant tag I got from the CCC said Matucana matanzus, but I know it's Melocactus matanzus. Why they put it down as Matucana I have no idea.
Feeding habits for all small globular cacti is the same. Dilute and not too often Or *very* dilute and as often as you like
The advice for "high potassium" is a mixture of folklore about getting a cactus to flower, and a safety net for over-feeders. If you're going to over-feed then best to use a low-nitrogen mix.
The advice for "high potassium" is a mixture of folklore about getting a cactus to flower, and a safety net for over-feeders. If you're going to over-feed then best to use a low-nitrogen mix.
--ian
- Steve Johnson
- Posts: 4526
- Joined: Thu Nov 03, 2011 4:44 am
- Location: Los Angeles, CA (Zone 10b)
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- Posts: 458
- Joined: Sat Oct 16, 2010 2:41 am
- Location: 40 south 7440 east Kanab, Utah (Johnson Canyon)
The MSU orchid fertlizer (as Iann says;very dilute)works well for me on Opuntia species but I have few other cacti. I grow a few Escobaria and Echinocereus native to this area as well and all seem to do very well on this fertilizer. Orchid culture is somewhat more demanding of good water and proper fertilizer than cacti but many of their requirements are similar. I only fertilize my cacti twice a year at most and with about 1/2 tsp/gal of the MSU fertlizer. Most of my cacti would grow fine without the fertilizer but I get almost double the pad development and flowers with the additon of the fertilizer given after good growth starts in the spring.
I should point out that all my cacti are outside "in ground" and not potted.
Dean
I should point out that all my cacti are outside "in ground" and not potted.
Dean
Albert Dean Stock,Ph.D.
- Peterthecactusguy
- Posts: 8862
- Joined: Fri Feb 19, 2010 7:49 am
- Location: Black Canyon City, Arizona
I add fertilizer to my outdoors cacti (Opuntia mostly) when they are ready to bloom to get them to produce fruits. I don't know if it works or not. (I use the Schultz cacti fertlizer). I also use that for all my potted plants every other watering and it seems to work fine and is a very low fertilizer. I Think it's 2-2-2 but I might be mistaken.
Here's to you, all you insidious creatures of green..er I mean cacti.