Slight WPM near harvest - Advice please

[honeysoi]

Hi all, hope all is well.
Clearly not for me as I'm back, lol.
I am close to harvest (1x ak47 auto, 1x Banana kush auto, 2x3 tent) and decided to whip out my blacklight pen i haven't really used. I have tip burn on on the AK and some leaf damage on the Banana Kush, I believe from pH problems. I immediately noticed the dead spots glowed green which I believe to me normal. After close inspection, I noticed blue around the dead parts. I chopped abit off, looked under a microscope and its some WPM. Here are some pics. The wpm is not visible to the naked eye.
Since the photos, I've done a defoliation and examined all the leaves. There is only slight wpm on the dead parts. These are all removed from the tent. My main concern is being so close to harvest. If there are no signs at harvest is there a reason to worry? From what I've read, wpm actually prefers dry conditions. Will this reappear during drying/curing?
What is my best approach for the next couple weeks before harvest. Thanks.

 

[honeysoi]

Couple more photos. I should also mention my conditions. Temp sits between 25-30°C depending on day temp, RH sits at 50% and my dehuey won't get it any lower. Air flow is very good, 3x aci fans, 1 below and 2 above.

 

[SmokingWings]

Since the photos, I've done a defoliation and examined all the leaves. There is only slight wpm on the dead parts. These are all removed from the tent. My main concern is being so close to harvest. If there are no signs at harvest is there a reason to worry?
What is my best approach for the next couple weeks before harvest.

Best approach is to start a preventative spray program. The one I use is an easy to make at home citric acid spray and can be used up to harvest. Mix some up and spray once or twice a day for a few days and then every couple of days till harvest.

I have found it pretty easy to get rid of Powdery MIldew when it is showing on fan leaves. The tricky thing is doing something about it if it is starting to grow on the sugar leaves especially right where they are going into or joining the bud itself.

The link to the recipe for the Citric Acid Spray is in the Thirp thread shown below. The citric acid crystals can be bought at many grocery stores. Ask "customer service" what shelf it is on. Smaller neighborhood hardware stores that sell canning supplies also have the bottles of citric acid. If you want you can do a google search to see what the bottles look like.

https://www.420magazine.com/community/threads/thrips.512473/post-5519939

The member who figured out the recipe also has a milder version but I do not have the link to that since I have been happy with the stronger one.

From what I've read, wpm actually prefers dry conditions. Will this reappear during drying/curing?

Powdery Mildew spreads the quickest during dry conditions. That is when the spores are easily broken off the main mildew and carried around by the lightest breeze. Then when the spore lands on a leaf it can wait until the surface gets damp from water or even high humidity and starts growing. It is said that by the time the gardener sees the mildew it has probably been there for several weeks waiting and just getting started.

You might want to consider doing a "bud wash" at harvest. This can really help get rid of dust, dirt, small pieces of dead leaves and it can kill off and remove hidden mildew. I do not have the link handy but maybe someone else does.

It should not reappear once the drying has started unless the harvested buds get damp or the humidity gets way to high in the storage containers for some reason.

 

[honeysoi]

Best approach is to start a preventative spray program. The one I use is an easy to make at home citric acid spray and can be used up to harvest. Mix some up and spray once or twice a day for a few days and then every couple of days till harvest.

I have found it pretty easy to get rid of Powdery MIldew when it is showing on fan leaves. The tricky thing is doing something about it if it is starting to grow on the sugar leaves especially right where they are going into or joining the bud itself.

The link to the recipe for the Citric Acid Spray is in the Thirp thread shown below. The citric acid crystals can be bought at many grocery stores. Ask "customer service" what shelf it is on. Smaller neighborhood hardware stores that sell canning supplies also have the bottles of citric acid. If you want you can do a google search to see what the bottles look like.

https://www.420magazine.com/community/threads/thrips.512473/post-5519939

The member who figured out the recipe also has a milder version but I do not have the link to that since I have been happy with the stronger one.


Powdery Mildew spreads the quickest during dry conditions. That is when the spores are easily broken off the main mildew and carried around by the lightest breeze. Then when the spore lands on a leaf it can wait until the surface gets damp from water or even high humidity and starts growing. It is said that by the time the gardener sees the mildew it has probably been there for several weeks waiting and just getting started.

You might want to consider doing a "bud wash" at harvest. This can really help get rid of dust, dirt, small pieces of dead leaves and it can kill off and remove hidden mildew. I do not have the link handy but maybe someone else does.

It should not reappear once the drying has started unless the harvested buds get damp or the humidity gets way to high in the storage containers for some reason.

Thanks for the information.
Is the citric acid mix safe for buds if it got on them when spraying the sugar leaves?
I have been considering a bud wash, although it kind of worries me with bud rot and such especially on the big colas.
If there are no signs at harvest, would you still bud wash? Thanks.

 

[honeysoi]

Update: just found another leaf with some wpm on the underside. I do plan on pulling these a little early based on previous harvests being abit to couch lock. I plan on pulling the Banana Kush in a few days and the AK in a week or so. Unsure on best approach. I have been considering a bud wash but concerned about drenching large colas

 

[SmokingWings]

Is the citric acid mix safe for buds if it got on them when spraying the sugar leaves?

The way I have understood it for years is that the small leaf points sticking out of all the buds are the sugar leaves and that they are called that because of they look like someone sprinkled sugar on them.

The citric acid crystals that are available in the store are a natural compound. They are used for home canning and commercial food preservation. The citric acid spray will need a few drops of liquid soap per pint which will act as a 'sticker' helping the acid crystals stick to the leaf surface as the water dries.

My reading on the spray is that it works because the water has become acidic enough to kill the powdery mildew on contact. The next day where ever there was a small patch of mildew there will be a dull white colored spot that does not wipe off. It almost looks like a scar from the damage the mildew did as it attached itself to the leaf and sucked the plant juices out. The acid crystals that form as the water dries will leave a acidic surface that new spores will not live on.

Most if not all the home remedies that I have found for treating powdery mildew call for mixing up an acid solution or making something that will turn acidic. The recipe mentioned in the earlier msg is probably the least expensive and strongest and is natural.

I have been considering a bud wash, although it kind of worries me with bud rot and such especially on the big colas.

The wash will help wash away spores that might still be there. Plus help remove dust, dirt, dead and still living insects plus their eggs and bits and leftover pieces of dead leaves after the trimming.

If there are no signs at harvest, would you still bud wash?

Yes, the advantages outweigh anything negative about a bud wash. So far I have not noticed anyone saying anything bad about doing the bud wash.

If you read through the main threads on Bud Washing you will notice that there are many who would not go back to skipping the wash at harvest time. It is now something they do each and every time.

 

[honeysoi]

The way I have understood it for years is that the small leaf points sticking out of all the buds are the sugar leaves and that they are called that because of they look like someone sprinkled sugar on them.

The citric acid crystals that are available in the store are a natural compound. They are used for home canning and commercial food preservation. The citric acid spray will need a few drops of liquid soap per pint which will act as a 'sticker' helping the acid crystals stick to the leaf surface as the water dries.

My reading on the spray is that it works because the water has become acidic enough to kill the powdery mildew on contact. The next day where ever there was a small patch of mildew there will be a dull white colored spot that does not wipe off. It almost looks like a scar from the damage the mildew did as it attached itself to the leaf and sucked the plant juices out. The acid crystals that form as the water dries will leave a acidic surface that new spores will not live on.

Most if not all the home remedies that I have found for treating powdery mildew call for mixing up an acid solution or making something that will turn acidic. The recipe mentioned in the earlier msg is probably the least expensive and strongest and is natural.


The wash will help wash away spores that might still be there. Plus help remove dust, dirt, dead and still living insects plus their eggs and bits and leftover pieces of dead leaves after the trimming.


Yes, the advantages outweigh anything negative about a bud wash. So far I have not noticed anyone saying anything bad about doing the bud wash.

If you read through the main threads on Bud Washing you will notice that there are many who would not go back to skipping the wash at harvest time. It is now something they do each and every time.

Thanks, I have easy access to citric acid at work. And yes I've been doing a bit of reading about bud washing, although most people re post the Jorge video. Only thing I noticed were the buds were quite small. Are there risks with bud washing with large packed colas?

 

[honeysoi]

I've also read alot of different things. Some say bud wash with baking soda, citric and h2o2, some say just h202, and the ratios are all over the place. Jorge video says 8 oz 3% into 5 Gallons. Some say 1:4 ratios of 33%. HUGE difference.

 

[honeysoi]

I have plenty of Potassium Bicarbonate and citric acid, apparently both kill wpm. If that's the case can I get away with the low h2o2 dose? Only have 24oz of 3%. What are the best dilutions for each of these please? thank you.

 

[cbdhemp808]

Your plants look great! What size pot they growing in?

I grow in mold central here in Hawaii, outdoor in greenhouses. I have found that PM on sugar leaves really doesn't cause a problem in the buds. If it's a really bad case, then you'll be trimming off more sugar leaf than you'd want to. Most phenos I'm growing now are PM resistant. Instead of trying to combat leaf mold and bud rot, I am finding strains/phenos that are naturally resistant, and having some success.

Purple Pineapple Express (Annunaki) is known to be 100% PM resistant.

 

[SmokingWings]

've also read alot of different things. Some say bud wash with baking soda, citric and h2o2, some say just h202, and the ratios are all over the place. Jorge video says 8 oz 3% into 5 Gallons. Some say 1:4 ratios of 33%. HUGE difference.

I have plenty of Potassium Bicarbonate and citric acid, apparently both kill wpm. If that's the case can I get away with the low h2o2 dose? Only have 24oz of 3%. What are the best dilutions for each of these please?

Some people adopt a method that matches what they have available. I figure most of those methods are going to do the job, maybe a bit of overkill, but not something that should cause any problem.

I am not going to say what is a best dilution but will give my method.

Use a citric acid spray once a day for the two or three days before harvest. Then at harvest do all the necessary trimming and cutting stems with a stack of buds to a manageable size based on the bucket. The vast majority of what I am growing are clones from clones so plants are usually kept small. Bud wash is a 4 step process in a 2 1/2 gallon bucket.

1.) Mix 3% H202 at 1 part to 3 parts water. Usually 1 quart H2O2 and 3 quarts water. Wash harvest and put in strainer. Dump and rinse bucket.
2.) Put 1 gallon to 1 and a 1/2 gallons of water in bucket. Put harvest back in bucket and add 1/2 cup baking soda (not baking powder) and swish the harvest all around. Pour in 1/2 to 1 cup of lemon juice and swish some more. The mix should foam up noticeably and I can hear it foaming. Keep swishing and when the foaming stops add some more lemon juice. When all the baking soda has been dissolved there will be no more foaming no matter how much lemon juice is added. Take harvest out and put in strainer to drain. Dump and rinse bucket.
3.)Fill bucket with 1 and 1/2 gallons to 2 gallons of water and rinse the harvest. Swish around and take break to put baking soda and lemon juice away. Swish some more, remove and put in strainer. Dump and rinse bucket.
4.)Repeat rinse step. Rinse bucket and put away.

Start to finish this part is about 15 to 20 minutes including clean-up and putting away of supplies, etc.

Let the harvest drain for 5 to 10 minutes with some occasional shaking of strainer or whatever to get as much water off. After awhile I spread the buds on a couple of window screens and turn on an oscillating fan. The fan does not blow air directly onto the buds but come close. The air movement from the fan is enough that there are gentle currents over the buds. I will move the buds around every 8 hours or so for a more even drying of any remaining water. When I figure the harvested buds have no more water in or on them I put them into a paper bag and put it into the kitchen fridge to start the "low and slow" drying.

My feeling is that the water temperature will always be best at room temperature. It should not feel cold, not even cool. Nor should it feel warm. When I put my hands into the water in any of the steps it feels like I stuck them into wet air since the water feels pretty much the same temperature as the air.

When other growers say that their harvest seems to have lost the smell of the terpines, etc. I understand what they are talking about. If the water is warm or even a touch over being just 'warm' it can start to cook the buds just like a fast blanching of any vegetable would do. Cool water, and especially cold water, will have a similar effect.

At this point I firmly believe that it is the temperature of the water than causes the loss of terpine smells that so many growers are worried about after a bud washing. With the controlled water temp I now notice that the bag of buds in the fridge are once again giving off the desired smells within 2 days. Open the fridge door to get something and in no time at all the kitchen smells just like I brought up a new harvest for trimming.

After the 'low and slow' fridge dry the buds go into jars. They might not be as green looking as when first harvested but the aroma is there and it is a fresher and cleaner aroma than when I used to dry without a bud wash. Open the jar and it just smells clean and piney or chocolatey or lemony or pineapple or sweeter or whatever, but no matter what it smells cleaner.

I am happy with this method.