I have seen this a few times now and I’m not sure what’s up.
It happens to 2 out of 5 seeds I try to germinate using rockwool. I’m wondering if this is a bad batch of cubes.
Basically, the seeds will develop a white fungus and then they don’t sprout, or sprout really unhealthy. The ones without the fungus sprout fine as normal.
I keep the seeds in rockwool in a humidity dome, temps right around 80. I even used some 3% hydrogen peroxide in my soak this time at about 30ml per liter.
Should i throw these cubes out? I’ve had them for over a year and they have been stored in a closet without being fully wrapped so maybe that’s the issue?
Hard to say if that is preventing the seeds from sprouting properly, but that cube looks oversaturated to me from the first pic.
Whether the fungus originates on the cubes, seeds, or in the air, it will only grow given the right conditions. Maybe try a gentle squeeze of the cubes after soaking to get rid of some excess water?
The cubes should be soaked and ph adjusted before use. Before using em soak em with h202 just to be safe then dump out that tub n soak em in ph water about 6.0. Til the water they sit in reads 6.0 after sitting a little while.if it goes up in ph empty n reset at 6.0 til it holds. Then proceed. Thats what i do anyways im no guru at this. The h202 by the time you dump it n add water is just lil extra oxygen for em.
They say 4.5 to soak em at. But i grow soil mix so i dont go that low on em. But directions are finish at 5.5 i think rockwool holds real alkaline. I finish at 6.0 to use in soil mixtures.
Do you cover the seeds at all, or is it ok if light hits them? I use a small piece of rockwool (you can see it in the picture) to cover the hole. I barely rest the cover over the hole so they don’t have to struggle to get past it.
I was supposed to be shaking the excess water out of the cube and I have not done that… For sure next test I’ll do it.
The fungus grows on the sprouts if they survive and they have like little mushrooms growing off them and they grow really slow and eventually I throw them out.
Nope. No need to cover em up. Push em in just a little bit more (not much)theyll be in shade for most part.
Some say point tip down cause thats where your taproot comes from. Usually i keep domes sealed til they pop n reach up for air but either way works. Do you have a heat mat for underneath? The fungus could just be from the seed stalling in those conditions. H202 wont kill seeds either. Some ppl actually use it 50/50 with water to pop seed. That eliminates your fungus thriving situations. Soon as they break ground allow air to them but keep rh up at 50+ for seedlings n veg Best i can think of. Hope it helps.
Cool. Maybe try shaking one or two, and squeezing out one or two (more dry). You could also try some in some and some out. If they all get this again its probably time to chuck those cubes.
Edit: also I like to fully cover seeds. Not so much for light blocking necessarily, but to ensure full contact with the moist medium on all sides.
Another thought would be to try inoculating the seeds with beneficials, to outcompete the baddies.
I dunk seeds in a very dilute hydrogen peroxide - water, rinse them off, then soak in dilute recharge until they sink, followed by recharge to moisten their paper towel.
Worth a shot if you have any beneficial fungi or bacteria laying around
Temps are good i think, stay 79-81 and really consistent. Sometimes as low as 77 but generally 79-81. I’ll check humidity in the space outside the dome but it might be kinda dry. I’ll definitely try a few outside this next round!
You gotta buck that shit on the seeds before those are going anywhere. I’d throw them in a shot glass with some water and a splash of hydrogen peroxide until they sprout tails.
I kinda said all these things in my first post. Is there a heat mat under them or do you have one you can put there? Touch of h202 kills your fungi breeding grounds and adds beneficial oxygen to the water for the seed. Oxygen does what to everything ? Oxidizes. Breaks down. It assists a hard seed in cracking by breaking its cell walls faster
No heat mat, but I’ll be using more h202 next test which is coming up here in the next day or two.
Since I had problems a month ago I’ve been using freebie seeds I don’t care about trying to figure it out, 5 seeds at a time…
I think the humidity dome is exacerbating a fungal issue that exists in the rockwool. So next time I’ll use h202 to sterilize the wool, and also leave the dome off.
Trying to only change a couple things at a time because I did have great germination rates until about a month ago.
I agree fully. Making a bunch of changes at once you never really figure out what was wrong or which change was the fix.
Do you have any safe warm surface you could sit it on? A little warmth really speeds things.
It’s not from the rockwool. It’s a stowaway on the hull of the seed. You need to sterilize the seed itself by soaking in water + hydrogen peroxide. Just a guess, but could have been harvested from a bud with botyrtis.
