farmergiles

One of the most common and problematic pests encountered by indoor mj gardeners are spider mites.

Twospotted spider mites, Tetranychus Urticae are the ones most often infesting grows.


Spider mites are arachnids, not insects. As adults they have eight legs.

The first signs of spider mites will usually be small brown spots on the leaves in the centre of small yellow circles.


The mites are very small and like to live underneath the leaves. The spots are caused by the mites sucking the sap from the plant. It is usually the resulting damage that can be seen easily rather than the mites themselves.
Another sign is webbing made by the mites (similar to spider webs, but more like a film of web).

This pic shows an extremely bad infestation as you can see from the webs.


If your grow looks like this, best to call in a napalm strike, lol.

There are quite a few ways of eliminating or controlling mites but if used improperly, the problem can be made worse. An understanding of the spider mite life cycle is important.
The adult females lay eggs. These hatch into larvae (which have six legs), which then shed their skins and turn into nymphs (eight legged). They shed their skins twice again before turning into adults. This whole cycle can take as little as 6 days. An adult female can lay as many as 200 eggs.



So one female could start off a population which could number millions in a short time.

When they are shedding their skins it is difficult to kill them with some forms of miticides- the miticide tends to stick to the shedding skin rather than the live mite.
Also, some miticides will only kill off one phase. So if (for example) you succeed in eliminating all the adults but don't eliminate the eggs then you are only setting them back a little, the problem will reoccur.

Spider mites are very quick to develop resistance to many miticides. So if only one type is used and they are not quickly eliminated completely, it is likely that they will become resistant or even immune.

Pretty bad huh?

__________________
Cultivate a stoic calmness

SageTree

Greenhouse horror story memories for sure.

__________________

farmergiles

By far the best way of controlling mites is to avoid them in the first place.

Spider mites can be found on many plants outdoors. If a grower has been outside, especially if gardening or tramping through scrub, woods etc then a shower and change of clothes should be taken before going anywhere near a growroom.

Likewise a shower and change of clothes is indicated if a grower has visited another grow.

If any new plants or cuttings are received, they should be quarantined elsewhere before being introduced to the growroom.

Spider mites can drift in air currents on their webs to move to new locations.

Spider mites prefer hot dry conditions.
If a growroom has high temps and low humidity, a spider mite infestation can reach problematic levels very quickly. Lower temperatures and higher humidity will discourage them.

There are quite a few ways of killing mites but they are all easier in the vegetative growth phase. Once the buds grow bigger there are more places for the mites to hide away. Some miticides should not be used in flower as they may well cause a health hazard if they are smoked.
So if a mite problem is observed, vegging plants should not be flowered until after the mites are eliminated.

__________________
Cultivate a stoic calmness

farmergiles

There are some natural predators which feed on mites.

Ladybugs (aka ladybirds) feed on all stages of spider mites (and quite a few other pests). If you find ladybugs on your grow then let them go about their business. They are our friends. They look cool too.
Ladybirds will probably not eliminate mites but they can help control them and are useful in flowering when other control methods can be a health hazard.
Ladybugs can be purchased and introduced to grows for control of mites and other pests.

The ones with red wing cases with black spots are the most common but there are a few other colour schemes too.


There are some species of predatory mites which feed by preying on pest mites. Different species will do best in different environments. Quite a few different varieties can be obtained. Research should be carried out to identify which are most suitable for given conditions.


Plant sprays-
A variety of sprays are effective in controlling mites.
Before application, the plants should be watered so as to reduce absorption of the spray into the plant.

Soap spray
A dilute solution of dishsoap (non- antibacterial) can be sprayed on the plants. Spray thoroughly paying especial attention to the underneath of leaves and hard to reach areas of the plants. This is fairly effective in killing mites. The plants should be sprayed down with water approx 20 mins after application, otherwise the residue may clog the leaf stomata.
This treatment should be repeated at 2/3 day intervals in order to catch any which escape.

Another spray recipe-
1/4 cup baking soda, 1/2 cup cider vinegar, 1 tblsp lemon juice, 2 drops dish detergent & 1/4 teaspoon epsom salts. The epsom salts should be dissolved in say half a cup of warm water- they might not dissolve properly in cold water. Add the whole lot to 1 litre of water. Spray plants as above and rinse after 20 mins, repeat every 2/3 days.
NB- this solution can sometimes burn plants. It may be best to test a small area of the plant first. If it burns, dilute further with water and try again.

More suitable spray ingredients-
Garlic, cinnamon, coriander, clove oil and chilli are also effective ingredients. It is a good idea to test a small area of the plants to avoid burning.

Tobacco tea can be used. Best to use American Spirit or some other type without too much crap in (don't use regular ciggies). Try about 3 or 4 grams per litre of water. Boil the tea thoroughly as tobacco can contain mosaic virus. Test a small area first to make sure it doesn't burn. Rinse after 20 mins or so.

ISO alcohol
This is very effective. High concentrations can be used but must be rinsed quickly. Be very wary of ignition- avoid any sparks or flames while using. The grow area shoul be properly aired to get rid of the vapours.
Concentrations as low as 30% should be effective and less hazardous.


Commercial Miticedes
Avid, floramite, pyrethrum based mitisides, neem oil etc.
These are effective to greater or lesser effects (avid is pretty effective but improper use has encouraged resistant mites to breed).
Always follow the instructions, wear appropriate protective equipment as directed. Ignore the hazard warnings at your peril. Be careful of using on flowering plants unless you want toxic buds to smoke.
Unfortunately, a lot of criminal commercial grows overuse industrial chems to control pests. If you buy commercial weed it could have dangerous levels of harmful substances.


Once you have applied your chosen spray or miticide w/e and it has taken effect, the dead mites and eggs should be rinsed off.

__________________
Cultivate a stoic calmness

farmergiles

Because mites breed so quickly and it is so hard to kill every last one, it is common for them to become resistant to any given treatment.

The best way to avoid this is to rotate a variety of different treatments.

So when you first notice an infestation, you might treat the plants with soap spray. Then you might go and get some ISO alcohol and treat them with that 2-3 days later. Then you might try a different spray recipe... and so on.

This will stop them becoming resistant to any one control method.

The same applies to using commercial miticides. You might get rid by just using avid but it is safer to use one or more different types with 2- 3 day intervals.

Don't assume you have eliminated them after one treatment whatever method you use and however thoroughly, as mentioned earlier they go through different stages from egg to adult, not all methods will kill all the stages 100%.

Good luck .


P.S. Oh yeah, nearly forgot- one more method. Mist the plant thoroughly with water. Cover the plant with a clear plastic bag. Make sure it is very humid inside. Tie up the bottom round the pot. Leave for an hour or two. The high humidity will kill mites. -NB there is risk of encouraging mould this way.

__________________
Cultivate a stoic calmness

Cerpin Taxt

I found out about spider mites at my recent greenhouse job, quite a number they did! Spent a few hours tossing all of the plants and quarantining the pots which held them.

Very informative thread as always good sir, I will add it to those I have on tap to refer to when I get the opportunity to grow

__________________
Step Back. Evaluate. Recognize.

"All memory is really a form of regurgitation of undigested experience."
-Alan Watts

mothernature

Well done, FG.

I would like to emphasize a couple of things.

Outdoors, there are different things nature does to keep spider mites at bay. Predators, like ladybugs, but also the wind and rain will help knock the bugs off of plants. Indoors, we don't have these ways naturally. Therefore, when a mites do infect the grow room, they can totally devastate the grow in a matter of days.

Also, prevention is, by far, the easiest way to cope with this terrible pest. If you garden in any other way, do your grow chores first, then mess in the yard.

__________________
Sometimes sleep is the best revenge- Luke

farmergiles

Zigzactly!


Cheers Cerpin, it'll be included in the growFAQ any day.

What measures apart from the quarantine do they take at the greenhouse place?

__________________
Cultivate a stoic calmness

SageTree

When we'd get them in the greenhouse we'd give them a dousing of chemies, although which one slips my mind, but probably isn't important here since that likely won't be anyone's solution.

BUT HEY!! speaking of solutions!!! Safers soap:




Used that on the landscaping scene and truly believe it works.

I'd mention to spray the area around the plant as well since those mites aren't always just on the leaf, but constantly getting knocked off by wind, rain and the like and crawling back on to the plant. 1 ft radius should do the trick. Follow application suggestions.

__________________

Cerpin Taxt

Hmm same deal as Sage; we'd use sprays on a very sporadic basis, but what exactly escapes me right now. For some reason I want to say calcium chloride, does that fit the bill?

__________________
Step Back. Evaluate. Recognize.

"All memory is really a form of regurgitation of undigested experience."
-Alan Watts

farmergiles

All I know about calcium chloride is that it is the main constituent of limestone and the anhydrous form is used as a deliquescent. It might be useful as a miticide but I haven't heard of such.

Yeah Safers soaps (or other similar soap sprays) are great; non toxic and useful against a whole range of pests.

It may not wipe out a mite infestation indoors but will at least help keep them under control and should certainly be considered as one method used in rotation with others.

The dish soap recipe mentioned further above should be similarly effective.

__________________
Cultivate a stoic calmness

SageTree

No doubt that when you go organic/friendly you have to put a little more on sometimes or be a little more vigilant with checking them early on ......









before you see webs forming.

__________________

Pharm Girl

I think this is an Emerald Beetle...ja think??

Attached Images

 

__________________

.....The Time has Come to 'Walk the Talk'.....~

......A message for ALL from the Deer Tribe...~

It is a great journey —
but you must do the walking
and have the willingness to change
and make the leap into
the next level of human evolution.

Become an inquisitive free thinking
individual that takes
responsibility for your life
and the spiritual accountability to live life to the fullest.

Fuck the Monkeys

SageTree

2024






THOSE LOOK MOST EXCELLENT!!!

__________________

mothernature

I think there's only one thing that can be done to get rid of the emerald beetle. I would highly recommend grinding it up and setting a match to it.

__________________
Sometimes sleep is the best revenge- Luke