Member of the family Cactaceae. Desert succulents.

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12
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2answers
2k views

How should I repot these overgrown and delicate plants?

I've got several plants that are probably overdue to be repotted. One of them is a cactus with lots of new growth and sharp spines. And the other is a jade where many more of the cuttings survived ...
11
votes
3answers
590 views

What should I do if the soil shrinks and separates from the flowerpot walls?

Recently we relocated a cactus into a new flowerpot. When it was planted the soil would evenly occupy the flowerpot and adjoin the flowerpot side walls. The soil isn't cactus soil, but just regular ...
10
votes
1answer
1k views

What is this white growth on my cactus?

I have several cacti growing in my yard and one (t. pachanoi, if it matters) has developed a white layer across the top of the plant. It is very fine and looks almost sandy, like perhaps a mould or ...
9
votes
3answers
274 views

How to manipulate a cactus with thick long spines?

I'm thinking of buying a cactus. Shops have a lot of those and one of the variables is the size and density of spines. Cacti with rare huge spines (something like 15 millimeters long and about 1 ...
9
votes
2answers
278 views

What's a good water system for my cactus plant during holidays?

I have a very resilient cactus that can be left alone for a month without consequences. Now, I want to leave it alone during two months and leave it some water system. I have seen little earthen ...
9
votes
2answers
3k views

Why is my cactus purple?

This has been going on for a while (about a year), one of my cacti has turned purple. I've just replanted it after its pot fell and broke (no, it did not spend the year on the ground). What is the ...
8
votes
3answers
649 views

What cacti can grow without cold protection in USDA zone 6b in Pennsylvania?

I'm in USDA hardiness zone 6b. I'm growing eastern prickly pears as outdoor perennials, and would like to grow some other cacti as well. From what I gather, cold hardiness has a lot to do with soil ...
8
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2answers
154 views

What is this cactus with paper-looking spindles sticking out all around?

I bought this cactus a while ago and never knew the name of the species. Can someone help me with the name of the plant? A small clone of it is growing on the top of the plant. Should I cut it and ...
8
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2answers
220 views

cultivating a cactus from cutting

I've recently gotten a san pedro (Echinopsis pachanoi) cutting as a gift. I'm trying to take care of it as good as possible, but I'm not sure if I'm doing it the right way. The situation is: the ...
8
votes
1answer
54 views

What is this epiphytic cactus with small orange flowers along the stems?

Does anyone know the species of this epiphytic cactus? Even the genus would be a step forward. Could it be a Disocactus sp.? The open flower is less than 2 cm (just under an inch) in diameter. The ...
8
votes
1answer
196 views

Does Rebutia grow better when grafted onto an Echinopsis?

I have tried growing rebutias before, and failed because the plants lacked vigor and grew slowly. Would they do better if I flat-grafted it onto a columnar Echinopsis, to increase vigor? Are there any ...
7
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1answer
1k views

Why Hasn't my Cactus Grown Deadly Spines?

I recently purchased a small cactus plant from my local store for about $5. I've been giving the cactus lots of sunlight and a good watering every week. I've noticed that since I bought it, the ...
7
votes
1answer
3k views

Why is my cactus droopy?

I have a cactus (pictured) which I bought about a month or so ago. It has been slowly drooping, although the tag said to keep it dry in winter and I have only watered it once when I re-potted it. The ...
7
votes
1answer
375 views

Do opuntia (prickly pear) cacti readily form hybrids in the wild?

I suspect the answer is yes, because they are the most diverse group of cacti. The reason I ask is that we actually have four varieties/species and I'm having a lot of trouble identifying them! The ...
7
votes
1answer
70 views

What is this white crust forming on my cactus during the growing months?

I live in the UK and have a Trichocereus bridgesii/Echinopsis lageniformis "monstrose" cactus that I bought from a garden centre 3 years ago. Every year in early summer several new stems grow from ...
7
votes
1answer
116 views

How to salvage a cactus plant that is half dead

This plant did very well for a year and bloomed. At some point I think I over watered it and it started looking 'dusty' and then parts turned black. I snipped off the worst parts and let it dry out ...
7
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3answers
82 views

Does anyone know what type of cactus this is?

Hi all, I recently bought this cactus but haven't had much luck identifying it. Any help or ideas would be very much appreciated. Thanks :)
7
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2answers
73 views

How can I determine if cactus seedlings are dead?

I planted some notocactus seeds sometime in September and many have germinated since then. A few weeks ago, there was an incident where some of my succulents may have experienced frost and I can't be ...
6
votes
1answer
321 views

What is this cactus with flat pads and spines growing in small patches?

I was given a cutting of a friend's cactus. It is growing in his front yard but he does not know much about it. His cacti are green and segmented some with red bulbs on top. I believe the red bulbs ...
6
votes
1answer
1k views

What are these brown patches on my acanthocereus tetragonus (fairy castle cactus)?

I've had this pair of fairy castle cacti for several years now, and they've done fairly well. However, I noticed today that they have developed brown patches over most of their stems and a few areas ...
5
votes
4answers
1k views

How to fix a broken cactus

I have been growing this guy for 6 years. He's gotten a little too top heavy and today has fallen over and the top piece (about 9") broke off. The break was very even. I have no idea where to begin ...
5
votes
1answer
125 views

White spots at the base of a cactus

Somebody gave me this cactus and I noticed that the base is getting white. Is it normal? Other information: I live in Canada The cactus is indoor and facing the sun all day I used soil for cactus ...
5
votes
1answer
55 views

How does one go about growing a cactus in a terrarium?

I've been searching the web online, and the ideas are all conflicting. Some websites would say cacti are unable to grow in glass jars because the heat trapped will cook the cactus, and other websites ...
5
votes
1answer
153 views

identify the type of cactus

My friend showed me this picture of a cactus and we would like to buy one. The problem is we don't know the name. Does anybody recognize it? Does it produce flowers?
5
votes
1answer
174 views

What should I look for when selecting lights for indoor cacti?

We grow cacti indoors due to the weather (UK). What should we look for when selecting lights? We have had mixed results with a new lighting system and have started to lose some. See one of the old ...
5
votes
1answer
309 views

Can any cacti be used as a scion on a non cactus succulent rootstock?

Anything in the cactus family can be grafted onto anything else in the cactus family, even jungle cacti to desert cacti. I've even grafted a Schlumbergera to a prickly pear. I would like to know, just ...
5
votes
1answer
186 views

How old do night flowering cereus get before they bloom?

I have a night flowering cereus that is about five years old. It is a foot tall and has a single stem. It is in a four inch square plastic pot. Is it going to flower anytime soon?
5
votes
0answers
35 views

What fertilizer should I use on agave and cactus?

I live in Canada and have several cacti and large agave plants. It's soon going to be time to bring them outside as the weather starts to warm up. They are potted in a mix of coconut fiber, sand, fast ...
5
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0answers
44 views

Repotting a cactus after flowering but before fruits

It is generally advised against repotting a cactus while it has buds or flowers on it. My Mammillaria prolifera has just finished flowering and it really needs repotting. But since it's a self-fertile ...
4
votes
1answer
44 views

Cactus with a growth

We have this cactus that I believe was supposed to be red at the top but is just dried and shrivelled but the stranger thing is the weird extra cactus growing out the top. Any ideas what it is, I ...
4
votes
2answers
76 views

Will prickly pear thrive under the eaves on the west side of my house?

The front of my house faces due west, with about a 2' overhang underneath the eaves. There is a 12' section between the northwest corner and the walkway leading to my door that has proven very ...
4
votes
1answer
116 views

Are eastern prickly pear cacti pads edible?

Are eastern prickly pear (Opuntia humifusa) cacti pads as edible as the kind you find in the grocery store (Opuntia ficus-indica)? I know the fruit is edible, if everything across the Internet I've ...
4
votes
2answers
168 views

How do I divide an overgrown Mammillaria cactus?

How do I divide an overgrown cactus (looks similar to Mammillaria vetula subsp. gracilis Preiff)?
4
votes
1answer
226 views

Can we root prickly pear pads that are sold in grocery stores as a vegetable?

Can I root prickly pear pads that I buy (presumably for food) in the grocery store? It seems like it would be a great way to get some thornless prickly pear cacti growing. If I were to do it, I would ...
4
votes
1answer
225 views

What's this cactus with large red and white spines?

I just got this cactus with large red and white spines and I'd like to know its species. It looks like a ferocactus emoryi except the spines are not hooked. But it could be something else as there are ...
4
votes
1answer
143 views

How do I safely eradicate mold without hurting cactus seedlings?

Here are some of my seedlings, sown a little bit less than a month ago. As you can see, there's mold starting to form. I am using the baggie method whereby the pot with the seeds is enclosed in a ...
4
votes
1answer
48 views

Is this sunburn or something else?

I've put my cacti for wintering into an unheated attic, by a window where the sun falls after 2 P.M and till dusk. Since it's negative temperature outside (so it's already winter in a sense) I didn't ...
4
votes
1answer
102 views

What is this cactus and how should I care for it?

I bought this cactus over two weeks ago. What is it's name and how should I take care of it?
4
votes
1answer
670 views

Cactus and Succulent in the same pot

I am looking to plant several cacti and succulents together in a single pot. Several of the plants will include a grafted "moon" cactus and a succulent "Eceveria Mazarine" there may be one or two ...
4
votes
2answers
75 views

How can I prevent Schlumbergera from dropping buds?

I recently bought a Schlumbergera from a reputable garden centre. It had buds on it when I bought it. It soon flowered and within a couple of weeks the flowers have all fallen off and the remaining ...
4
votes
1answer
90 views

What are these growths on my winter hardy Opuntia?

I received some winter hardy prickly pear pads from a friend last fall. They rooted well, survived the winter well (better than many other plants around here), and are putting out new growth. On the ...
4
votes
1answer
59 views

Why is my cactus drooping? [duplicate]

My cactus has gone all droopy and I don't know what the problem is. I've moved into a place with more light and I water it enough but I don't know what is wrong with it.
4
votes
1answer
117 views

What columnar cactus species I should select as a rootstock for a Rhipsalis standard?

I want to make a standard(1) with scions from a Rhipsalis pilocarpa, or mistletoe cactus. I need a rootstock that: Is columnar Is unbranched Has good longevity (at least 20 years) Can adapt to high ...
4
votes
1answer
370 views

Why has my cactus has turned red/ beige at its base?

One of my cactus turned red at its base about a year ago and it has since spread upwards. Some websites say it is a natural ageing process but I doubt so because it is still so small! Now another of ...
3
votes
3answers
129 views

What is the white stuff on this cactus-type plant?

I have had this plant for more than 10 years now but I do not know its name. What is the name of this plant? The issue is that this plant has a lot of white areas, as shown in the pictures. These ...
3
votes
3answers
291 views

How to save this blue cactus?

I am unaware of what type it is, I bought it at Wal*Mart, so I was rather suspicious that it had been improperly stored, but I don't know. The base seems very rotted, which I think means that I need ...
3
votes
2answers
223 views

What is this cactus with flat oval pads and very short spines?

I bought this cactus yesterday. I want to know its name to research how I should take care of it. I'm in a rather cold city (Zanjan in northwestern Iran) with long winters, so I think it's better if I ...
3
votes
1answer
205 views

Why has my cactus yellowed and softened, and how can I help it live?

I had a cactus at work since the end of March. It is my first cactus and I don't really know if I was watering it correctly or if I missed something else, but now it's turned yellow and became softer. ...
3
votes
1answer
133 views

How should I prune a cleistocactus that got too tall?

When I have a slender, columnar cactus like a Cleistocactus (pictured below), and it gets too tall, How can I prune it, to get it back to a manageable height?
3
votes
1answer
997 views

Why are leaves falling off of my Prickly Pear cactus?

I just moved into a new home in Phoenix, AZ, and now have a lot of cacti to tend to. I do not know their care history, or how much/how often they are watered. One of the largest Prickly Pear cacti ...