1000'th topic in the thread - the $1000 threat - Red spider mite

[Socksnsandals]

I had RSM on some non-weed plants in the garden in that glorious summer of 2018 but have not come across it before or since.  It is a known greenhouse pest and a bane of some indoor growers' lives. Now I have a greenhouse with a couple of autos in there rather than out in the garden and with the higher temperatures and low humidity am keeping a sharp eye out for the borg.  How many greenhouse growers have had problems with RSM?

[KillaChronic]

Only had them once. I stupidly used old bamboo canes for support and the mites came out of them.

I bought some predator mites online. This sorted them right out, would definitely do this again in future.

Different opinions online as to whether the mites would turn into such a large problem compared to an indoor grow with mites. I wasnt prepared to wait a d risk it though. 

[Socksnsandals]

2 hours ago, KillaChronic said:

Only had them once. I stupidly used old bamboo canes for support and the mites came out of them.

I bought some predator mites online. This sorted them right out, would definitely do this again in future.

Different opinions online as to whether the mites would turn into such a large problem compared to an indoor grow with mites. I wasnt prepared to wait a d risk it though. 

 

First time I met RSM was indoors in the kitchen when they colonised some Datura stramonium (Angel's Trumpets, grown for the flowers and their scent, not the antimuscarinic receptor side-effect heavy trip you get by drinking a tea made from their leaves - very dry mouth, blurred vision with giant pupils, flushing, tachycardia and wild hallucinations - a friend at school in the '70s enjoyed the playing fields covered in grand pianos but not the thick black hairs he saw rapidly growing through his cricket trousers, nor the hell-hound that was after him later but that's another story).  The RSM laid waste to the Datura, a small citrus tree, and everything else in there and re-emerged the following year so I know how destructive they can be and that they are around in the wild as well as in grow rooms.  Am now quick to order the predator mites if I have any worry that RSM are about - but there are tiny spiders (well, same family as RSM are arachnids too) which are probably beneficial and which make fine, but less dense webs between growing tips of young plants and which can make you worried that there are RSM. 

[inapond13]

I get RSM every year in my greenhouse and have learned to control them.  Predator mites are great and not that expensive.  Get them before you need them and RSM are no longer a problem.  They can sometimes take a week to be delivered as are often only harvested weekly.

 

The first time I grew in my greenhouse I was hammered by RSM and was a complete noob.  They totally suck the life out of plants so must be eradicated.

 

Check your plants daily for RSM.  React immediately!!!

[Socksnsandals]

@inapond13 thanks, yes, having seen what they did to our indoor non-weed plants I'm very vigilant and got predators for those in the past but was too late.  From the lack of responses to the thread I assume that RSM has not been a big issue for most greenhouse growers. 

 

Do you get the predators before you have seen any evidence of RSM or do you order the moment you spot them?  Having seen how devastating they can be I'd be worried about the time lag between seeing them and the predators arriving, especially as the latter take their time to build up in sufficient numbers to defeat the borg (if both can grow exponentially in perfect conditions then, unless the doubling time of the predators is faster or they consume their prey at a sufficient rate then an established infection will win of course).  One can't use conventional insecticides like permethrin whilst waiting the arrival of the predator army because not only are RSM semi-resistant but more importantly the predators are (from bitter experience) highly susceptible.

   

If you had RSM the first year in the greenhouse then you will never be rid of them (methyl bromide no longer being available) so an anticipatory policy of ordering predators before you see any RSM would be wise, though they may go hungry if there is no prey. 

[OldFord]

I only grow outdoors & in the greenhouse and experienced RSM once a few years back.    I now have a lady bug house in the greenhouse thats populated and i look after them  

 

My outdoor patch has 3 lady bug houses , 1 eah side and 1 in the middle of all my ladies.   The wife feeds them on white & green fly off her roses and a bit of peach from her tree they love it !!

 

Not had a single issue since the spotted ones moved in !    The big ass spider in the greenhouse keeps all other crawling & flying visitors at bay ........ all except the pheasant we caught stealing the low hanging peaches  

[Socksnsandals]

@OldFord https://www.pheasantfordinner.com/consumer/blog/baked-pheasant-with-peaches.aspx

 

When I was a boy with an air rifle I shot a woodpigeon sitting in a tree in our garden (I don't shoot anything now).  As I recall it weighed about a pound and had 4oz of lovely fresh marrowfat peas it had stolen from someone else's garden in its super-full crop.  It was probably too stuffed and snoozy to think it worth flying away as I crept towards it.  Well, waste not, live off the land etc - I cooked it with the peas as a side dish.  Some may say gross, but I didn't want to waste either the pigeon or those peas!

Edited June 10, 2020 by Socksnsandals

[OldFord]

20 hours ago, Socksnsandals said:

@OldFord https://www.pheasantfordinner.com/consumer/blog/baked-pheasant-with-peaches.aspx

 

When I was a boy with an air rifle I shot a wood pigeon sitting in a tree in our garden (I don't shoot anything now).  As I recall it weighed about a pound and had 4oz of lovely fresh marrowfat peas it had stolen from someone else's garden in its super-full crop.  It was probably too stuffed and snoozy to think it worth flying away as I crept towards it.  Well, waste not, live off the land etc - I cooked it with the peas as a side dish.  Some may say gross, but I didn't want to waste either the pigeon or those peas!

 

No thank you   @Socksnsandals,   my old man used to do game quite a bit in the north of jockland ,  i just can face eating it now    

The pheasants a regular along with a heron that loves to stand atop of the pond mesh and drool over the koi ,   we also get some local kites try their hand at the koi too.

 

We had a small female fox with a bad leg moved into the mower shed and stayed there for about a year, got to the stage i  could feed her by hand and she would play with the dog,  she had a litter then vanished a few months later.   She visits every few months and always brings a present     

[inapond13]

On 08/06/2020 at 7:57 PM, Socksnsandals said:

@inapond13 thanks, yes, having seen what they did to our indoor non-weed plants I'm very vigilant and got predators for those in the past but was too late.  From the lack of responses to the thread I assume that RSM has not been a big issue for most greenhouse growers. 

 

Do you get the predators before you have seen any evidence of RSM or do you order the moment you spot them?  Having seen how devastating they can be I'd be worried about the time lag between seeing them and the predators arriving, especially as the latter take their time to build up in sufficient numbers to defeat the borg (if both can grow exponentially in perfect conditions then, unless the doubling time of the predators is faster or they consume their prey at a sufficient rate then an established infection will win of course).  One can't use conventional insecticides like permethrin whilst waiting the arrival of the predator army because not only are RSM semi-resistant but more importantly the predators are (from bitter experience) highly susceptible.

   

If you had RSM the first year in the greenhouse then you will never be rid of them (methyl bromide no longer being available) so an anticipatory policy of ordering predators before you see any RSM would be wise, though they may go hungry if there is no prey. 

I have ordered my predators for RSM today.  I haven't seen a single one but I don't want to take the chance.  My auto's are as big as any photo I have previously grown and looking to get over 10 oz of these 4 girls only planted April 20th, so not yet 3 months old.  Spent £18.50  for 

Amblyseius andersonii

  which did me proud last year.  Will get delivery in 2-3 days and spread the around the branches.

 

Btw, my first greenhouse burned down and I built a new one in a different location and I got RSM the first year in the new one also.  Just the way it is :-)

[Socksnsandals]

Interesting.  I've had very few pests (a couple of blackfly and some slugs and snails) in the greenhouse in this, my first year.  The humidity has been pretty high all year except for a few days during the May heatwave and the only time I had RSM in the garden was that amazing summer in 2018 so I have been fairly relaxed. 

 

On the other hand, the moisture brings the risk of mould now they are in flower so have just got a dehumidfier and am looking at its effect via a wireless weather station (£9.99) with the outside temp/humidity sensor in the greenhouse. Looking good so far, but the relatively small amount of heat it generates is sufficient to make the more sensitive auto-openers want to open which would defeat the object so I've disconnected those.  That won't be an issue if we get clear skies or later in the year when night-time temperatures drop. 

[Socksnsandals]

Well, I have discovered that this sizzling weather has brought out the RSM in the garden (and on the weed plants in pots which I move about the garden) as it did in 2018.  Fortunately all the top buds on all the autos in flower have already been harvested so the remaining lower branches will make it to the finish regardless.  I have ordered predators to try to control my one auto which is in preflower and in case they are lurking hidden on my LST'd photo in the veg plot, plus, more importantly, all the peppers etc in the greenhouse.  Next year I will, like @inapond13, get prophylactic predators in advance of any visible infestation.  In the cold early summer when this thread started the weather didn't look as if RSM would emerge and as the greenhouse was new I hoped (and still hope) it hasn't been colonised yet but will work on the principle that if they are in the garden then they will eventually be in there too and will take care to wash hands etc before examining the plants inside so as to help prevent me transferring the Borg from the outside plants.

 

Gardening is constant warfare against organisms from multiple phyla (and viruses, not that we can do much about them - and it is debatable as to whether they are organisms or not).  Slugs, snails, aphids, mould, RSM, cats, squirrels, pigeons, the ever-present threat of humans in uniform, and this year, an insect attack on the gardener relaxing in the garden at dusk, with dozens of mega-itchy gnat bites to complement the arachnids / ticks from visits to potential GG plots. 

[Socksnsandals]

Fussing over the canna I took my eye off the other plants in the garden.  Thought the sunflowers had a bit of nutrient deficiency or perhaps some mildew and then realised to my horror that the recent super hot spell had brought out the RSM in force.  Fortunately only one of the canna has a mild infection and the predators are apparently in the post but I culled several sunflowers - too far gone.  Warning: Content may disturb viewers.