[luvaduck]

It seems a few of us Aussie outdoor growers have had issues with mould recently, so I thought I would start up a thread to get heads together, and maybe help reduce a most disheartening problem.

I'll begin with the problems I've encountered, my observations, and my conclusions. Keep in mind I grow in the wet tropics, where relative humidity can be in the high 90's for months on end. I would also like to point out that I don't like to use fungicides, or any chemical input for that matter, and very rarely do.

In seedlings, the most common issue I find is "damping off". In really bad cases, this can roll a seedling before the first set of true leaves appear. Seedlings generally appear sluggish and under nourished. Generally my issue has been waterlogged seed raising mix. I have also noticed an higher incidence if I don't sterilise my pots (I use 75mm tubes for germination). The brand of mix for me is important, I swear by searles as I never seem to have problems with that. Occasionally I will use my main potting mix (which I blend myself) as a base and then cover the seed with the finer seed raising mix.
The way I normally deal with damping off is to discard plants and potting medium, unless they are really important strains, in which case I will drench the soil with the recommended rate of mancozeb. I know this stuff is toxic, but I figure that this is the worst I use and it is normally in the first couple of weeks of growth, so little harm done? Worse walking down a city street and inhaling benzene..

During growth the only real fungal issue I have come across is root rot. In my situation this is due to soil type ie too heavy, sticky clay.. I find perlite to be a fantastic investment. It's cheap if you can find it in bulk, I normally pay $30 for 100 litres, and it is really light if you have to carry it long distances. That and coir fibre to amend native soils, just add ferts and, viola!

Flowering issues are the real let down. Nothing like running some real exciting strains then loosing a great percentage to rot. For me powdery mildew is not a great threat, although it does occur. The main issues I have are caused by rain and excessive humidity, and this brings on grey mould, cause by botrytis fungus. Fungicides are never really an option I go for here, although if I did I would use eco fungicide. It is potassium bicarbonate, which is a food grade product and about as mild as it comes. Any mould stuff I have goes to oil for the missus skin cancers.

Strain selection and plant health are the most important factors in my opinion. The right strain with mould resistance and a flowering time late enough to miss the wet weather has been the most important to me. In regards to plant health, ease up on the ferts, lush growth looks great but at the expense of soft plant tissue. I prep beds and do very little until harvest, except foliar spray with various products and ALWAYS include neem oil, until after the first month of flowering.

Hope you all have bumper crops. Please put your own 5 bobs worth, the more knowledge the better.

LD

[canna.ballistic]

Luvaduck, a very timely post ... seems like it has been a tough year for bud rot. I generally agree with your strategies, but have a few extra comments.

I am in a coastal subtropical location, which is subject to both high humidity levels as well as extended periods of rainfall (as in nearly everyday for a number of weeks in a row) during summer and into autumn ... bud rot during flowering is also my main issue, powdery mildew not so much.

Prevention is easier than cure, although prevention itself is not always easy.

Healthy plants and healthy soils are a primary objective ... plenty of great info on ICMag to assist on these topics.

For my conditions, I have found the sativa-type strains with longer flowering periods (say 12 to 16 weeks) to generally be less affected with bud rot than the shorter flowering hybrids (i.e. 8 to 9 weeks). I believe this is primarily due to the weather cooling down and the humidity being lower during the latter stages of flowering when the buds are fattening up, and are most susceptible to bud rot. The 8 - 9 week plants finish up around the end of March, which coincides with wet, hot, humid conditions ... whereas the 12 to 16 week strains finish from the end of April through to the start of June, when there is less rain, less heat and less humidity.

I would guess this is similar for your tropical climate as well, although southern growers in the temperate zone with autumn and winter rainfall would probably benefit more from the shorter flowering strains.

The other challenge is finding good growing locations. The best place to grow a plant to minimise the potential for bud rot or powdery mildew is in the open on high ground where it can get lots of sun and air movement to quickly dry dew, rain, etc from the plant. However, this type of location is also the most likely to be found during the annual helicopter flyovers, and so has to be used very sparingly and carefully. The locations which are least likely to be detection are on the edges of / within forests, along gullies, etc, which are all subject to less sun, less air movement and higher moisture levels ... perfect for bud rot.

Unfortunately, living in the Nanny State of Oz, means I will keep growing my couple of plants each year in the bud rot areas, so as to avoid detection.

[Dog Star]

Having almost always problems with clones since they are under a humid dome
and i forget to give them air more frequently and they develop those molds and
another funghal diseases.

But i solve everything with a Horstail tea,spraying 3 days in a row for best results.

Hurd also for one Australian plant,shoek i think its shes name helps in a same way
as Horstail for anti-funghal.

Here are few good advices.. https://www.livingforestfarm.com/trea...anic-remedies/

[bambi]

hi there; bud rot is a bummer yeah,
however i find some clone plants with big tops and very little leaf to bud ratio are less likely to mould as one with more leaf in its tops as this is where we 1st see it appearing right,

If a tiny or bud leaf pulls out of the bud with ease then id be worried & look further with a magnifing glass, if there one week away from being ready i pick that top asap & keep it out of a room or away from the crop,
outdoors its best to tunnel your way into high bush & dig out the middle for the plants, this way youve wind protection / people protection / critters like rabbits seem to eat whats growing through a thigh high fence we used to find, why they dont jump over it like a possum i dunno ?

I know a nice looking + fast blooming - 6.5 - 7 weeks in or outdoors handles 30 deg'c heat quite good for days on end, doesnt seem to mind the cold either & keeps its buds hard with a good high folks love in Nz thus far,
Im doing a final test trial soon if your keen for a look give us a bell , the plant is a Mikado polyhybrid with a stronger high & flavour is green onion & red rose & does have a reddish colour seen once dried,
Thing is i find most important is it can be harvested around April 7th instead of the 8 - 9 weekers taking as long as the end of may or early june when rain can ruin a crops tops.

youl figure something out, we usually find a way around things we love so much.

[Brother Nature]

I've always found topping your plants a few more times than you'd prefer can assist with mold issues outdoors as well. You'll reduce your final yield but much less than if they get moldy.

[420bears]

i found mould on one of my buds today i quckly stripped it all up cut out the mould and chucked it my buds are drying atm

[Goldust]

hopefully wasnt a large amount worse ive thrown away was a ounce

[ozzieAI]

every year i throw plants away due to mould...but living in the tropics it is to be expected during the wet season...i haven't found a strain that hasn't gone mouldy, from sativas, hybrids and indicas they all got it...

i have tried all sorts of sprays and chemicals but none has been successful unfortunately..

[Dog Star]

You tried Australian shoek..?? its a plant that have same action like Horstail,same anti-funghal action.

You tried a baked soda spray few days in a row?


Not one funghal disease can grow if you exchange a PH surface,with this moves
you will not aloud good enviroment for funghal grow as they cant procreate on
this kind of surfaces that are pretreated in a dry days.

[Teddybrae]

Here's a new product from Nutri-Tech Solutions in SE queensland.

(top right hand of page) that's the prices pencilled in.

it's a blend of Potash and Silicon. the Silicon hardens cell walls to

reduce insect damage which is often where mould will start in yr

heads. that's the claim anyway ...