Questions20 Jul 2010 08:07 am

Hiya guys,
Every bit of advice you’ve given me has been so spot on,
now I’m having a problem that is making me so mad.
They are farmed by my many many ant colonies in the yard,
and every time any of my succulents produces a flower,
BAM! Black aphids cover it, and I just clip it off,
because it’s so nasty. Even my giant Kniphofia flower stalks are not immune.

What would be a good plan of attack so I can enjoy my succulent flowers
for awhile before the black aphid plague descends down upon them?

Thanks so much.
PS. Your advice on Sluggo was great.
I have to reapply often, but the snails got the message.
Stay away from my succulents!

With Aphids on succulents you have a couple of choices:

Hose them off the blooms with a soft spray of water, being soft bodied insects they are easy to dislodge and then you can really blast them when they hit the ground. Think Aphid soup! I usually hold the bloom stalk with one hand and spray with the other. It is sort of messy, but usually works.

Use insecticidal soap, and then after they are dead you still have to wash them off, since they die in place, still piercing the plant with their vampire bites, their zombie bodies are still annoying. But the soap usually leaves eggs unharmed so you may need to retreat before the blooms are done.

Use a more aggressive insecticide like Pyrethrin which will kill them and most of the eggs, but is absorbable by you… so use with care and caution!

Of course as you know they are farmed like dairy cows by the ants, so you also need to work at knocking down the ant population which with the Argentine Ant Super Colony that is eating California will be difficult, try adding some ant treatments around the succulents as well.

Take care,

Questions05 Jul 2010 11:30 am

Hi Peter,
Can you please identify this Aloe for me?

Thank you!

You have what looks to me like Aloe mudenensis. They are growing really nicely there. Sweet!

Questions01 Jul 2010 11:41 am

Hello Peter,

I hope you and Hap are both doing well and business good. I need some help with an offspring of our large Opuntia which has a white spoor like growth on it. The plant doesn’t seem to be hurt by it at all, but none the less I wanted to know what it is and what to do about it. Let me know if you have any knowledge or advice. As we need some small items I hope we can get up your way soon.

Take care


The Opuntia has a bad infestation of Scale Insects. They are sort of Limpet-like vampires of the pest world. You should be able to get rid of them, but it will take a bit of work. First, spray the branch down with straight rubbing alcohol (or Vodka) and then loosen them with an old paint brush, the alcohol will dissolve the shellack they coat themselves with when they glue down as adults. After doing what you can with the alcohol and paint brush, rinse with a “stern” jet of water from the hose, this will help blast off more them. Follow up with a good spray of Neem Oil at 1-2% solution, you can get this at any good nursery, as it is used on Roses as a natural insecticide and fungicide. Respray with Neem after a week at least three times to break the life-cycle of any hold outs or eggs that survive. Make sure to spray the Neem in the evening and not during the hot sun, as the oil needs time to disperse as to not cause burning of the plant. You should also fertilize that plant and give it an extra drink to boost it’s natural immunities.

Take care,


Questions28 Jun 2010 11:09 am

I am a subcriber to your newsletter and was refferred to you by a friend. She told me that if I email you a photo of a plant, that you would be able to identify it. Can you please help me identify this cactus and Please tell me what I need to do to make it green and healthy as it has been showing clorosis (yellowing) for sometime now. I rescued it off the street corner as someone was throwing it away. I have repotted it with cactus soil mix about 4 months ago.

Any info, would be greatly appreciated.

Thank you.

You have a Cereus peruvianus and as you say, it’s clear that you have “rescued” it. We use slow release organic nutrients (we sell our own mix, too), so if you haven’t fertilized yet, now would be a good time. (If you’ve used something stronger, that can possibly be a cause of the yellowing.) When our cactus look yellow after the winter, we also will add Kelp Meal.

Questions16 Jun 2010 06:55 am

I have several echeveria and graptoveria which I bought from you and have just finished planting in my new garden. They look so much alike that I’m wondering what is the difference(s) between them, especially differences in what the mature plants will look like. (I was hoping for flat to the ground hen and chicks appearance, but perhaps I won’t be getting that?)

Thank you.
Carol (Vallejo)

It depends which species you have, but generally the echeverias are the hen and chick style, stemless and on the ground, while the graptoveria do sometimes get a trailing stem. If you send me photos, I can confirm what your individual species will do.

Questions15 Jun 2010 08:56 am

Hi Kevin,

When you have a chance, can you tell me what these are? I got them from different places.

The first one was given to us, has beautiful bloom;

Second one hitch-hiked with another plant I bought, with a big round root under all that tentacles and had a ring of tiny yellow flowers a while ago;

3rd one I got from Target, reminds me of someone wiith a bad hair day;

4th one spread like waves/snakes.

I cannot find these from any books I have, so thought you might be able to help. Is it OK to trouble you? or is there another source I can ask about plants?



Here are the attached photos:









You have:
149. Crassula falcata, also known as the propellor plant.

536. is a crested Euphorbia, possibly Euphorbia flanaganii

537. is definitely Euphorbia flanaganii, also known as Medusa’s Head – would certainly qualify as bad hair…

538. Tephrocactus articulatus v. papyracanthus, or the Paper-Spine Cactus.

Questions07 Jun 2010 07:23 am

HI, I was wondering if you could tell me what kind of plant this is, and if it is unusual for it’s size. It was growing for some time then this tree like appendage came shooting out of it. It is well over the top of our 1 story home. Easily close to 2 stories high. Picture is included. Thanks for your response.

Vista, CA


Your plant is an Agave that it is starting to bloom. It looks like it is an Agave americana or “Century Plant”. The blooms will open soon and look amazing, the stalk will eventually (over the next year or two…) dry out and be a sculptural corpse… Agave bloom stalks were often used as alien trees in old science fiction films. Agaves grow for a long time (but not really for a century) and then bloom and die. However there should be “Pups” or baby plants around the base of the blooming mother plant that will repeat the cycle, as Agave have a habit of cloning themselves before trying to do “sexual reproduction”. If there is another Agave bloom in you area and you have Agave moths, you might even get seed pods. If not the flower stalk will sometimes try another cloning strategy and grow plantlets where the blooms are, that eventually helicopter down and root in where they land.

Take care,


Questions05 Jun 2010 07:30 am


My son is very worried about his cactus. He has had it for about two years and it started to turn black (please see attached photos) two weeks ago. We live in Wisconsin, and his cactus receives about 8 hours of sunlight a day. Any advice would greatly appreciated.

Thank you,


The cactus is mutant Gymnocalycium that is grafted on top of a Hylocereus stem (the green part). It is a chimera pair so that the bottom graft can feed the top bright-colorful part that lacks chlorophyll since it was likely exposed to gamma radiation to kill the chlorophyll and bring out the wild otherworldly color. The sad reality is the mutated part is generally short-lived because it has compromised immunities and can’t build all the proteins it needs.

The black infection showing in the photos is likely a fungal infection (it could also be a virus). If it is a fungus it may respond to being treated with a fungicide. We use Neem Oil, which is usually effective, while having low (to none) toxicity issues around mammals (us, kids, pets…). Neem Oil is used in toothpaste and cosmetics. You should be able to find a ready-to-use Neem Oil product at your local nursery. Follow the directions and spray it down well. Retreat after a week. Hopefully it will stop the infection, but the top graft will always be scarred. If the infection continues the top graft may fail and turn all black; if it does cut it off and treat the green base with Neem. The Hylocereus base is actually a cool jungle cactus that can be treated more like an orchid and if it starts growing new arms it can eventually bloom and even fruit, which are those cool and tasty looking “Dragon Fruit” you might have seen at the grocery store.

Good luck,

Questions&Reader Photos29 May 2010 07:33 am

You never know what kind of common names you’re going to get from a cactus.

(Here’s) a picture of a cactus I have that blooms once every May.  Four tall white flowers that look like umbrellas. I would like to know what kind of cactus it is. Thanks.


That’s an Echinopsis alright, formerly known as a Lobivia. As for the particular species, it’s hard to tell from the photo, but it might be Echinopsis subdenudata from Bolivia.

Questions27 May 2010 08:48 am

Hi, we had a cactus planted in our front yard about six months ago. It’s getting browned and hard at the bottom, but not mushy (which I thought would indicate overwatering). The browning is working its way up the plant, but if it IS overwatering, of course I don’t want to continue to contribute to that problem by watering it more thinking it’s too dry.

Any suggestions!? Thanks!

Matt B
San Diego

It’s a little hard to tell exactly what I’m looking at there. It’s probably just barking, i.e. the plant is turning into a tree and creating a trunk at the bottom with bark. On the other hand, it could be an infection. The key question is: Is the area soft or firm? Firm is good, soft is rot and that would be bad.

If it is soft, then given the location of the rot, you probably need to cut the plant down and get rid of the root mass. You can then save the branches, let them dry in shade for a week or two, and then plant them in a fast draining cactus soil.

A warning: This is a Euphorbia and it has caustic sap. Wear protective clothing, long gloves and eye protection. Don’t get any of the milky white sap on you.

What rot in a Euphorbia looks like.

Peter, I really appreciate your response.

It’s hard – very hard – and inching upward even though I’m not watering the plant at all, so it sounds as though it’s barking.

Again – thanks so much!!
Matt B

Questions26 May 2010 08:46 am

Hiya guys,
I just got back from my tour of the US,
and my buddy gave me some cow’s tongue opuntia when I was passing thru New Mexico.
I was wondering if the fruit is edible and the same as standard prickly pear.
I never see this in the Bay area, is it rare out here?

All opuntia fruit is edible, just some taste better than others, some are less spiny and easier to get at than others, and some are already bottled in fancy sweet vinegars made in Italy.

Questions24 May 2010 06:40 am


I’m heading to a wedding and would like to bring a hand-made succulent arrangement as a wedding gift.   What are some succulents that can survive the lack of sun that Eugene has most of the year?  Are there good resources that show which succulents would work well in that climate zone?


P.S.  I’m thinking it can be an indoor arrangement to help regulate the ridiculous amount of rain it would get otherwise outside in Eugene.

The best options for low-light succulents are the Haworthias. They tend to be small, but there is a lot of variation in the look. Also, there are a number of Crassulas, green Aeoniums, and even some Aloes that can handle fairly low light levels, though not full shade. For outdoor in Eugene, there’s a book called “Hardy Succulents” that list lots of succulents and the colder zones they can handle.

Blogs&Questions&Reader Photos21 May 2010 03:04 pm

Hello… I’m a regular reader, and very occasional commenter on your blog… you may remember me from a prickly pear cactus jelly post you linked to… [Ed: Yes we do remember!] regardless…

I bought this plant in July of 2008. When I bought it, it was labeled Mammillaria species… and that’s it. Nothing else…

I’ve included 4 pics… 2 of the plant when I first bought it, which I posted on the blog in hopes that some kind, kind person out there knew or could blindly guess the species. They couldn’t…

there’s also one with blooms from last year, and a current pic showing fruit…

If you could help me ID the thing, I’d really really be grateful… thanks for your trouble…

Claude from Random Rants and Prickly Plants

I typed up a response and saved it in drafts, and now its missing, so I don’t know if you’ve already received an answer from me, but you have a lovely Mammillaria perbella. The fruit in one of the photos is edible, though tiny, and only if you haven’t used chemical insecticides. If grown outdoors, it would be way more spiny, but yours is looking great.

Also, see here on Claude’s blog another picture of the Mammillaria in question. And don’t miss out on the beer can garden post. Really, you don’t want to miss it.

Questions06 May 2010 08:56 am


I had this cute lil plant that was doing just fine until a few days ago i decided to let it have some direct sun for a few days. I’ve had them in the pot for about 2 months on my back porch which gets mostly indirect light all day rather than direct blasts of sun. I haven’t watered it for at least a week and a half, if not longer.


Over the weekend, I brought it out on a little table in the backyard and it seemed fine Sat-Sun. Today was my first day in the backyard since Sunday and poor little plant- what’s happening?? It’s all yellow and limp, looking sad… Is there such a thing as too much sun? Can you help me figure out what’s going on, and if there’s something I can do to help the situation?

Thank you!!

Your plant has a sunburn. Generally, you cannot take plants from shade or from indoor into direct sun – they need to be “hardened off” which means getting them a little sun at first, and gradually bringing them out into more sun over a week or two.

At this point, its hard to tell if they will survive, but get it out of the full sun, into a bright location, and hope for the best. It will definitely lose most of its bottom leaves, but hopefully there will soon be new growth from the tips of the plants.

Questions&Reader Photos04 May 2010 06:43 am


I really enjoy your blog. Really getting into succulents now. Went to a garage sale a few weeks ago and bought this cactus . Could it be a rat tail?? Or an Aporophyllum??


Would appreciate any help you can give me.


It turns out your plant isn’t a cactus at all, but a stapeliad (in the asclepiad family) and the species is Huernia macrocarpa, also known as the dragon flower. Check out the cute as a button carrion flower here.



Questions21 Apr 2010 10:34 am

We saw Euphorbia Characias ssp. Wulfenii and Euphorbia x martini on your blog. Are they evergreen plants? Since they’re listed as perennials, we’re worried that they would die back or be half-dead in the winter. Our project is in San Jose, where winters can get down to 24 degrees F.

Thank you,

Both of these are hardy and evergreen in San Jose, and we do have E. martinii in stock (as well as a bunch of other evergreen spurges). We do have some other Euphorbias that are deciduous, but not these. Perennials here in California are often evergreen; we use the designation perennial (survives year after year) in distinction to annual (survives only one year), and we also refer to whether plants are evergreen or deciduous.

Actually, we don’t use the label “annual” on any of our plants, since this is California where lots of plants that are annuals elsewhere are perennials here and we choose not to grow any outdoor plants that don’t survive the winters.


Questions20 Apr 2010 07:16 am

I purchased this lovely little variegated agave (Tag just said Agave ‘mediovariegata’) on a recent trip to California. One pup was visible at the soil surface. When I pulled it out of the pot, I found half a dozen more pups trying to grow out the drainage holes (see attached photo). How is best to handle the subterranean ones? Can I separate them now, or should I put it in a bigger pot and let them make their own way to the surface?

agave mediopicta

Much thanks,


The name is Agave medio-picta “Alba” and it will eventually get 6 ft. across. Congratulations on all the hidden babies. You can go ahead and separate them all now if you want, and get each pup into its own pot with a fast draining cactus soil. Gently pull them off, and they should separate without needing to cut.


Questions&Reader Photos17 Apr 2010 07:31 am

Yes we can!

First, we have the preliminaries:


My name is Liz and I had been looking on your site for awhile to find out the type of wonderful cactus that I have. I have had this cactus for a long time but never knew what type it was. I have looked into books and browsed around I have seen many that look similar but can not pin point it. I was wondering if I could email you a picture and you could help me identify it?

Thank you,

Hello Liz,

We would be happy to try and ID your plant, email a photo or two and we will do our best.


Now we have the main event:

Good Afternoon Hap,

Thank you for taking the time to do this for me! Here I sent a couple of pics!

New Image2 New Image1

And finally, the ID:

Hello again Liz,

It looks like you have a nice Echinopsis aurea or commonly known as “Golden Easter Lily Cactus”. Native to Northern Argentina. It can be a bit rot prone so watch so be careful not to over-water and next time you repot I would suggest a chunkier cactus blend that is mostly 1/4″ lava or pumice, since these guys will often turn to mush if they stay too wet.

Take care,


Questions14 Apr 2010 09:15 am

Hi Hap,

Hope you’re doing well.
I had a couple of aloe vanbalenii that had root rot. I trimmed off as much as I could to expose some white/green flesh. Can I just plant them into the ground now (the soil is well draining and dry).

2010-04-06 11.16.06



Yes, replant in fresh fast draining soil and keep on the dry side for the next few weeks. They should reestablish pretty quickly if the weather turns back to be warm and sunny… if it stays stormy and cool they would likely prefer to be potted and under a rain shield of some sort for the next month.

Take care,

But wait! There’s more! (more…)

Questions&Reader Photos07 Apr 2010 07:02 am

Apparently we’re not the only ones to get this question; the email was also sent to Berkeley Hort, Magic Gardens and Westbrae. I hope we gave the best answer.


I recieved a plant with flowers that look like the picture attached to this email. I don’t know the plant’s name so I am not sure how to care for it. I was told it was a dancing orchid but most the care sheets I found online for dancing don’t look remotely like the flowers in the attached picture. Do you know the name of the plant in the attached photo? Most of the flowers along its long stem are dying now, should I be cutting the stems?? Could you maybe direct me to a website with information on how to care for the plant in the attached photo?




You orchid is a Brassia, or commonly known as a “spider orchid”.

Brassia pretty much just takes standard orchid care… here is a link with specific information.

You can trim off the spent bloom-spike after it dries out, but don’t cut it off until then as they can occasionally re-bloom from the same spike if they are really happy.

Take care,

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