Beginners mistake quadfecta--golden barrel help please!

[tomo]

I bought this guy online and repotted him a couple of months ago and have come to realize I've made at least 4 beginner mistakes--wrong pot (plastic pot, but with no drain hole), wrong soil, incorrectly replanted, and to top it off, about 5 days ago, I slightly over-watered it. Since the soil isn't drying out, I decided to take a chance and try to repot it again. I'm concerned about repotting it twice within two months but I figured it was better than letting it sit in damp soil?

Aside from the issues I've mentioned, I also noticed a couple of odd things on the cactus. First are these small white-ish spots I've marked with red arrows. Is this normal? Is it mold or something else I should be concerned about? Then we have the odd large blob in the blue square. No idea what that is.

I'm hoping I can fix the problems and would really appreciate some input and advice. Also any recommendations about soil mix, like would a mix of 50% soil, 50% lava/pumice/turface be good for this type of cactus?
Thanks in advance!

[BarryRice]

Get a good, strong magnifying glass and look at those wooly blobs. Pop one. Is there goo inside? I'm afràid you have another problem--mealy bugs.

[tomo]

Thanks for the reply. Wooly blobs--are those the ones I marked with the red arrows? egad, mealy bugs, something new to worry about. I'll check tomorrow and post again.

[DaveW]

Yes they are mealies, use a spray on contact insecticide before re-potting or even afterwards, because you don't want to have to wet the soil using a systemic insecticide before the roots are re-established. In any case systemics are ineffective if the plant is not growing and the roots active to take them up.

You should be able to find the "bug gun" spray types that say they kill mealy bugs at your local horticultural centre or where they sell cacti, like this:-

http://www.diy.com/departments/scotts-b ... 02110110:s" onclick="window.open(this.href);return false;

Even if you normally use systemics these spray on contact types are handy for individual treatment in winter and when the plants should not be watered and the soil wetted. Just look on the "gun" to see if it's instructions list mealy bugs.

[BarryRice]

Don't worry about the big brown blob. As long as it is hard, it is just old tissue. If it soft and gooey, the plant is in big trouble.

[Ron43]

If it is mealy bugs, dab each one with rubbing alcohol and it will kill them. Keep watching and if more appear hit them with the alcohol again.

[tomo]

I looked at the wooly blobs today and used some rubbing alcohol on a q-tip and actually saw a mealy bug! Thanks for alerting me to that problem! I think I've taken care of them for now, but I'll keep checking daily, and I've separated this cactus from my other plants (it's a small collection). And some good news! The big brown blob is hard, glad I don't have to worry about that. Also good news, when I took the cactus out of the pot yesterday, the roots were damp, but today nice and dry. I hope to repot properly in the next few days.

Thank you all for your helpful insight and advice, really appreciate it!

[greenknight]

I would rinse the roots clean of that stuff, let it dry for a few days, and then pot it with proper cactus mix.

The good news is it's a nice healthy-looking plant. Kill off the mealy bugs and it should do great.

[DaveW]

Mealies you often have to treat repeatedly for a while since most insecticides kill the bugs but their eggs seem immune to them and so you get a new batch hatching out later. Even systemics do not last long in the plants these days. There used to be a systemic in the UK called "Long Last" which claimed it lasted up to a month in the plant, so hardly what I would call long lasting since you needed more than one application a year to eradicate the bugs!

Interesting quotes from the following link:-

"Favorable environmental conditions (e.g., temperature) and plant growth may increase the mealybug population. For example, plants irrigated frequently that receive high concentrations of a nitrogen-based fertilizer tend to be more susceptible to mealybugs. Water-stressed plants may also be more susceptible to mealybugs. Furthermore, mealybug females feeding on plants receiving high concentrations of a nitrogen-based fertilizer may lay more eggs than usual."

"Systemic insecticides, depending on the type, may be less effective on mealybugs than on aphids or whiteflies. This may be associated with mealybugs not ingesting lethal concentrations of the active ingredient because they feed within the mesophyll tissues or on plant stems."

http://www.ksre.ksu.edu/bookstore/pubs/MF3001.pdf" onclick="window.open(this.href);return false;

[tomo]

I'll rinse the roots and wait for them to dry before repotting, thanks for the suggestion!

Hmmm judging from the article about mealy bugs, sounds like maybe the wrong soil and my recent over-watering caused the mealy bug situation? Hopefully if I know what caused it, I can avoid (or at least minimize) the chance of them returning. I'll watch and continue to treat any future wooly blobs with rubbing alcohol.

Glad to hear otherwise the cactus looks in good shape!

[DaveW]

I have always found mealies tend to prefer sickly plants, such as ones with lost roots etc, more than healthy ones, but will infest both. But it is always worth checking if the plant is not thriving whether it has other problems too.

[iann]

I have always found mealies tend to prefer sickly plants, such as ones with lost roots etc, more than healthy ones, but will infest both. But it is always worth checking if the plant is not thriving whether it has other problems too.

Maybe sickly plants are sickly because they have mealies

Almost certainly the soil is too rich and you overwatered, but your plant has mealies because it has mealies. I don't know where you got the plant, but mealybug is rampant in UK garden centres. The only one I've been to in the last 10 years or so that didn't have them on their little display of pricklies with Santa hats and googly eyes was a place that had burnt down and just been rebuilt. You probably don't need to go to that extreme to rid yourself of the little pests. Since you have the plant out of soil, you can soak it for a few minutes (or hours) in a dilute soap solution. That will kill almost anything, although perhaps not eggs. Systemic treatment may not be very effective on a big fat plant with no roots, but you should consider it for later in the year.

You now know what a mealybug looks like. The big ones hiding in the wool are adult females and they've almost certainly laid eggs already. The young nymphs are almost invisible to the naked eye but there may be hundreds of them for every adult you see. Keep your eyes open and spray the plant at intervals until they stop appearing, or treat with a systemic. Be extra-vigilant with any new plants you bring in.

[tomo]

Thanks for the latest replies. I bought this cactus from a seller online, is it possible it could have had mealy bugs when it arrived? And then my mistakes made the situation worse.

I have some new photos to share. Today I rinsed the roots and got rid of most of the soil, and noticed that most of the roots are on one side, and almost no roots on the other side. Plus, the part where there aren't any roots, it's kinda wrinkly looking? I remember it looked this when it first arrived two months ago, when I first repotted it. But now I'm wondering if this is the sign of some other problem? Is it normal/OK for roots to grow like this? Or is this plant doomed?

[greenknight]

They may have had a bunch of plants crowded together in a nursery tray and it had more space to grow roots on one side. It's normal for the old part at the base of the cactus to shrivel up and become corky, I think you can just see is better on the side with no roots. As long as it's not soft and mushy there's no problem.

It may have had mealies or their eggs on it when you got it, no way to tell now. Is it doomed? I don't think so. The roots look healthy, I think it should do fine.

[Steve Johnson]

Is it normal/OK for roots to grow like this? Or is this plant doomed?

I wouldn't write it off just yet, but you haven't gone far enough to correct the situation. Been through this before, so here is what I'd recommend:

1. Clean as much crap out of the roots as possible. I use the tip of a plastic ballpoint pen cap, although any pointed object with a blunt end will do. Next, soak the roots in 1% Hydrogen peroxide for 15 minutes. This kills any potential plant pathogens, and it'll promote faster healing of any roots that were damaged. Gently rinse the roots in running water, then let them dry before repotting in fresh, dry mix.

2. Pumice is excellent, and a good number of growers do well with that and nothing else. If you live in a hot, dry climate, you should probably add some soil for better moisture retention. Best to use a soil with minimal organic materials, although commercial potting soils are so heavily composted with plant wastes that getting anything decent for cactus mixes has become difficult.

Once you address the root cleanliness and mix problems, let your cactus settle in and do not water it until the growing season is underway. Here in SoCal that's only 3-4 weeks away, although I don't know where you live, so you could be looking at April or May. I agree with greenknight -- if you treat your golden barrel right going forward, it should be fine.