Mites in Hippeastrum.

Bessemer City, NC(Zone 7b)

While attending to my amarylli, I decided to remove some areas of red specks, both on the outer green scale and in the dried leaf bases around the neck.

As I cut away the outermost layer, which had scabby red lesions, I saw some sort of bulb mite! I had thought that the red scarring was due to mites and now I knew. I'm certain the bulbs had the infection when I got them. I guess I just thought it was normal at the time (several years ago) not knowing about bulb mites, red blotch and so on, or the red was hidden under a dried tunic.

Anywho, the mites are visible to the naked eye (with good or corrected vision, of course) though they are teeny-tiny (scientific term). Just a dark splinter or hairlike little critter. And they move very fast!

The disturbing thing about this is that the one I found was between the scales, down in the bulb. I only found one, but will treat all my bulbs with some miticide shortly. I hope that it will reach them between the scales, but I just don't know. I'm going to see if there's a systemic treatment for them.


Frederick, MD(Zone 6b)

Please post any information you discover. I haven't examined them that closely yet, but I do have red lesions on some of my WalMart bulbs that I bought last fall. I've got some Avid on order, might try that if I do find mites... it has a somewhat systemic effect in that it is absorbed by leaves, so maybe it would be absorbed into the bulb as well.

Bessemer City, NC(Zone 7b)

Avid is what I am planning to use.

However, the "hot water treatment" is said to be very effective in erradicating bulb mites. I plan to treat my bulbs with the HWT at some point if the problem doesn't seem to be resolved with the Avid.

I'll keep you posted.


Frederick, MD(Zone 6b)

Are you going to dip/soak the bulbs in a solution of Avid?

Bessemer City, NC(Zone 7b)

Is that what you're going to do?

I'm going to apply by spraying. I plan on directing the spray into the layers at the neck or wherever they are, trying to get it between the layers as well as a generalized spraying over the bulb, soil and pot. They aren't badly troubled and I think that should really slow them down.

I may repeat this in the fall after the temps cool down. I'll check them closely after they've been in cool rest and will treat them with hot water just before I bring them into warmth to restart them.

Haven't read any info on dipping or soaking with Avid. Do you have a link to any?


Frederick, MD(Zone 6b)

The first thing I'm going to do is examine those bulbs more closely to see if I really do have mites, LOL... I hadn't thought it out much beyond that. I ordered the Avid because of a couple of African Violets that were looking suspect, although on further examination & research I suspect the cause is something other than mites....

With AVs, you can spray, or you can dip the plant... The makers of Avid actually recommend dipping I think both so that all leaf surfaces are covered and as a way of minimizing toxic exposure (you're more likely to breathe it in or to get it on exposed skin if you spray than if you dip wearing gloves & long sleeves).

I thought dipping made sense with the amaryllis bulbs as a way to get the solution down between those outer layers...

Bessemer City, NC(Zone 7b)

I think you're right about dipping. Seems more effective. And not inhaling toxic mist is a good thing! Avid is not to be toyed with!

I guess I could just dip the whole plant, pot and all into a big bucket of solution. I have some Hosta that have foliar nematodes and I think I'll do them at the same time. Good idea and thank-you for mentioning it.

I was leaning toward spraying because I didn't think of total immersion and was going to wait until I repotted so I could just dip the bulb and whatever foliage was there. With immersion, I can get a thorough treatment of soil, roots, bulb, the lot!

How long do you think they should remain in the solution before removing? 2-3 minutes? 5?


Frederick, MD(Zone 6b)

I don't know.... the instructions I've seen just said "dip" not "soak".... I'm thinking a dip and a quick swish should do it.

Anyone using Avid... Please follow the safety precautions... Wear good chemical gloves (not thin little food service things), long sleeves, eye protection, and a mask wouldn't be bad either, especially if you are spraying.... Good ventillation too...

Avid is toxic stuff, and it's not something that should be used routinely as a preventative. But it has the reputation as being one of the best miticides out there, and if you have hard to control mites like cyclamen mites, it's worth doing... alternative is to throw away all infested plants.

Avid is also expensive, at around $100 for 8 oz, but a little goes a long way... if I'm remembering correctly, 1 oz makes about 12 gallons of solution.

Bessemer City, NC(Zone 7b)

Thanks Critt and you're words of caution when using Avid is well-taken and is good sound advice when handling all restricted chemicals and most others as well.

The thing that alerts me to the possible presence of mites, is the bright red, "peppered" appearance on exposed portions of the bulb scales. Also, as you peel off a dried or damaged scale, you frequently see that underneath there is undamaged blemish-free green with a strong point of division between the exposed portions (with the red lesions) and the spot-free part that was underneath it. Of course, some reddening can be the result of mechanical action, but the mite damage seem to have a brighter color and appears to be scar-like. Knowing what you're bulb has or hasn't been subjected to as far as scapes or other mis-handling or mishaps will also help in the diagnosis.

So will a good magnifier!

In spite of my finding a mite under a scale, they may not be so good and getting between plump, hydrated and otherwise healthy scales. For all I know, that fast-moving little imp could have just scooted under there as I removed the top scale.

When I find another live mite, I may try to see is I can identify it (tarsenomid or other) or I may just say "good-bye, whatver you are."


Frederick, MD(Zone 6b)

Well, I definitely saw a mite running around in the saucer underneath one of my WalMart amaryllis bulbs today... It was dark but otherwise looked just like the photos I've seen of cyclamen mites, and as you noted it was speedy! The Wal Mart bulbs have been isolated from the other pots. I ordered my Avid a week ago, so hopefully it will arrive soon.

Edited to add, I wasn't sure if you already had Avid at hand, Robert... If you need just a little, Dmail me & we'll work out a trade. :-)

This message was edited Mar 21, 2006 6:39 PM

Frederick, MD(Zone 6b)

OH! Also meant to ask... could you please post directions for "the hot water method" of ridding bulbs of mites? No reason not to try the nontoxic approach first... :-)

Bessemer City, NC(Zone 7b)

I'll be glad to.

How much detail do you need as far as setting up a treatment "facility" goes?

Or do you have all the basic concerns covered already?

What *are* the basic concerns? Glad I asked! ;-)

You must be able to hold a quantity of water at a temperature of (in this method) 115F evenly throughout for about two hours. This means having a way to keep it at an exact temperature and possibly keeping the water circulating so that aren't any hot or cold spots.

Since you are having to keep each bulb in the water for (in this example) two hours, it makes sense to do them all at once rather than one at a time, unless you only have a few and have the time to spare. You decide.

The main thing is having a *constant* water temperature to avoid damaging or even killing the bulb and to effectively eradicate all insect pest and their eggs including those nasty bulb mites.

I started writing out a much longer version of the how-to that goes into the setting up of a home treatment "center" using whatever is available ("making do") but I'll wait to hear from you as to what you really need.

The down-and-dirty is basically what I said before:

Large (8" circumference) bulbs are treated in water @ 115 F for 120 minutes and smaller healthy bulbs about an hour, but various times are used professionally in both cases.

Let me know if you want me to go from the ground up with all the details, and I'll post them here.


Frederick, MD(Zone 6b)

I have a large canning pot in which I've successfully kept water hot within about a 4 degree varience... At this lower temperature, I could probably limit the varience to a couple of degrees. Is any amount of varience permissible with this method? Or will temperatures of 116 or 117 degrees kill the bulb?

Will foliage survive these temperatures, or is this best done with a dormant bulb?

I don't want to ask you to type out a long, complex description here... but if you have additional information, or a link to additional information, I'd appreciate it!

Bessemer City, NC(Zone 7b)

I don't mind....

Great idea about the canning pot! Do you keep the temps evened out by stirring? I think using a metal (oh what is the word?) "thing" to keep the bulbs off the bottom of the pot, sort of suspended in the middle would be good so that they're away the heat source. Is that what you're planning? Let me know what you're thinking and keep posting to this thread.

The 115F is just one of several temperatures used commercially. The problem is that temps of 117-118F for too long can damage the emerging bud, but if that's ok with you, then it's not so big an issue.

In the Netherlands, 120 mins. at 115F is "standard" while a common treatment in Israel may be 90-150 mins. at 110F. (The differing times adjusted to the size of the bulb and the lower temp, AFAIK. ) Actually, Dutch growers consider 117-118F as ideal for killing mites and thrips, but use the lower temp to avoid damaging the unemerged buds.

So the lower the temp, the longer they are treated, it seems.

Veronica Read, Hippi Maven of Great Britain proscribes 120 mins at 115F for large healthy bulbs (over 8" circumf.) and 60 min for those that are healthy and smaller than 8" circ. Add an hour to each time for unhealthy bulbs.

Foliage is generally cut back to 4" above the neck in growing bulbs.

Along the same line, any damaged roots are removed and any old leaf bases removed especially if rotted. It's best to treat otherwise healthy bulbs seperately from ailing ones. If you have an old bulb with a thick basal plate it can be cut back to one half inch: baddies love to hide out in the leaf scars there. While cleaning up your bulbs, try to keep water out of the neck and dry them asap. They should be totally dry within 24 hrs. to avoid rots and fungi.

When you treat them, they are completely immersed. After taking them out of the water, drain with the neck pointed down, not straight down but at an angle of somewhere around 30-35 degrees or so. At a nice slant. Paper towels can help here..... When drained, stand them up to finish drying. They should be in a nice airy place to hasten drying.

They can be potted up right away as some growers do, or it it's in season and you do it as such, they can be dried off for their cool rest as other growers do. They are initially dried for 10 or more days in warmth, then put in the cool dry for storage. (55F or so).

I plan to pot them right back up asap and grow them on. I'm thinking of how to keep the roots from drying out too much while the bulb drains......

It seems that a good time to treat them would be after the first flush of foliage has matured and growth is on hold, as they do.

And of course, ditch or bake all the old soil as it is prolly just full of mites and wash your pots in hot soapy water with maybe some clorox added. You know the drill.

Clean the whole are where your plants have been or put them somewhere else entirely. Etc and sanitarily so on.

I hope that helps.


Frederick, MD(Zone 6b)

That helps a lot, thanks!

I'm thinking that if you dig bulbs at the end of summer and let them go dormant for a couple of months (I know not everyone does this), that might be an ideal time for the hot water treatment, to make certain you're not bringing mites inside with the bulb. That way, their "drain & dry" time can just be the start of the time they're sitting on an airy shelf anyway -- no need to worry about the roots drying out since that's fine then.

I would probably go for the longer time / lower temperature method.... while I don't mind an occasional deformed bud, damaging the buds in *all* my bulbs would be hard to take! ;-) Especially with the larger bulbs, I'm think that brief excursions above 115 would probably be OK... you just don't want to be keeping the temperature that high.

I have a canning rack, and I may put some wads of foil into the bottom also (wrapped around the rack) to make quite certain the bulbs don't touch the bottom of the pot. If you have a big pot with a steamer basket, that would probably also work well... I do have one, but it's not as heavy as my canning pot, and a heavier pot will keep a more even heat. My stove is electric (gas is easier to control), but it's one of those sealed glass top ranges, so the burners are pretty responsive & easy to keep even. I may test my Nesco roaster full of water to see if I can keep the temperature more even on it. The more volume & mass in the pot, the smaller the temperature swings.

I think there are digital thermometers available that have alarms on them.... like a candy thermometer... Having one of those on hand set to 116 (or whatever you decide is your max temp plus 1) would let you know when the water started getting too hot without the need to stare at the pot for 2 hours.

For the WalMart bulbs that have mites now, I'm thinking I may just go ahead and treat them with Avid. :-)

Bessemer City, NC(Zone 7b)

I have a bit of Avid here but will have to check to see how far it will go. Thanks for offering to trade.

I also have some Kelthane and may try that first. There doesn't seem to be a lot of them, so maybe it will at least slow them down, lol.

Spider mites like it light, hot and dry and favor wood in their environment. They're discourages by misting and syringing of the foliage. Outdoor I spray the hose on mite-prone plants and some of them really respond well to the spraying (like Mandevilla).

But the bulb mites like it cool and damp. One thing I've read to help control them, is keeping the bulband leaves as dry as possible with careful hand watering and keeping them spaced as far apart as possible so that overlapping foliage doesn't give them their dark moisty hide outs. This goes for groups of potted plants and planted out ones too. Crowding is probably more likely to create problems in bedded Hippis due to all the foliage and rain.

So, where I am right now is: I'm pretty sure I'm going to spray with kelthane several times till mid-summer or so, and if they seem to be free of mites, I'll stop there. I have only six or so bulbs that might be affected out of 15 -20 (haven't counted lately--I went to the Southern Spring Show and bought a "few" more....). I'll spray the lot of them anyway, whether they show signs or not as they've all been cheek-by-jowl at the windows.

Good luck to you. Keep me posted on what's going on with you and your hot water.


Frederick, MD(Zone 6b)

The more I think on this, the more I am considering just throwing out the bulbs that came from WalMart... they bloomed, I enjoyed them, and they were something like $3 each... I'm not saying they're not worth the effort to save, but I definitely won't be planting them out with the uninfested bulbs.

Bessemer City, NC(Zone 7b)

I've gone back and forth, as well, as is prolly evident in this thread.

The hot water deal may be the most effective method in commercial production due to the environment being what it is. On that scale, it may be too difficult to apply sprays effectively and then there's always the toxicity issues to workers, chemicals lingering and so forth.

Actually, there is less red scarring on my bulbs now than there was before, so maybe the damage was done prior to my ever getting them, and the pests are the last gasp of the infestation.

I'm going to rant a bit now. Keep your hair covered, you wouldn't want it scorched. LOL.

A German Hippi grower on another site was saying that most Dutch bulbs are shipped with live mites in them. They multiply mostly while in storage. As a result of their activity, fungal infections occur more frequently. The li'l buggers open up the tissues to allow spores to enter and actually put it there themselves form bits that cling to their bodies. He said that in their natural environments, fungal attacks like red blotch seldom occur. It occurs as a result of other conditions that set the bulb up for it. Conditions like mite infestations.

There is a reason why discount stores can offer such good prices: they get great deals on bad product! Product that a producer couldn't sell to businesses who deal in top quality.

Here's an example of what I observed in a Wal-Mart. I was looking at their amaryllis bulbs, the kind that come pre-packaged, seeing if I could find a white one. They were all blooming in the packs and NOT ONE of the "white" ones was blooming white! They were *all* red. Don't recall who packaged them. I guess most people would let it slide, not getting the color they wanted, and don't ask for a refund so that kind of thing goes on and on. Maybe it's the same with bad bulbs. Hey, you can always blame their failure on the purchaser!

I would expect to find lesser quality bulbs at such low prices, but I'm thinking that diseased and infested etc. bulbs find their way out of some unscrupulous growers' warehouses and into the market more often than than not. There is a temptation to sell bad bulbs (etc.) at a very "attractive" price rather than dumping them and losing the investment of time and money. Doing the right thing can be costly........

Am I being pessimistic? Dunno. I'm not trying to make a case, but you do hear a lot of stories of problems with cheap bulbs..........If it doesn't come in with the bulbs, where the heck *does* it come from?

I like to believe that plant importation laws are in place to prevent the spread of diseases and pests being brought in on imported bulbs. Could some diseases and pest problems be ok'd for some reason? "Well it's just that old blotch, it's already here anyway and it isn't a problem to the consumer, so...." Maybe there's just no way to effectively inspect the zillions that are imported annually for mites, spore, pest eggs etc. Too few inspectors? Maybe it's all a "payola" scam.......

Somebody has to know the story. Somebody between here and wherever they come from, out of the many hands that handle them, someone knows. They're just not telling.

I'm tired of ranting. I'm going to bed now.

Good luck with your bulbs!


Frederick, MD(Zone 6b)

Robert, I agree.... I think we sacrifice quality control for savings, and those "wonderful cheap plants" from the box stores don't always end up being such a bargain when they bring "hitchhikers" home with them!

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