Hi all. I’m hoping you can give me some input here. I have been using the paper towel/baggie method of germinating seeds. I’ve had a lot of problems with black mold this year - not on the paper towel, but on the seeds. I attribute this to not soaking long enough in H2O2 when preparing the seeds (5 minutes is just not enough!). Anyway, what’s done is done.
I’m still getting germinations though - not a huge amount, but enough to keep me happy. The problem is, when I transplant many (50%) of these split seeds from the paper towel into the soil (Scotts Seed Starting Mix), they never sprout, but rather rot in the seed mix. Sadly, I’ve lost all of my Lynn Anderson x Memorial Day seeds this way. It’s particularly sad since I probably had a 75% germination rate on this much anticipated cross! Since I’m doing all of this in the house, I’m reluctant to use Captan which has a Danger designation. Any input would be GREATLY appreciated. H202 seems to help a bit, but it seems, not enough to save most. Once they sprout, they’re fine and I don’t lose any to damping off.
Thanks for your help!
By the way, I used a r. Californica seedling for testing purposes, and it seems you can actually water these little guys with a 50% strength solution of H2O2 (3%) without apparent harm.
Here’s what works for me. The method is derived from info from the RHA & modifications to suit my conditions. I soak my seeds in water in a small container (recycled prescription container) with a splash of H2O2 for one or two days. You know if you’ve used too much H202 when it starts fizzing & the top blows off. Not to worry, it won’t harm the seeds.
I use the smaller snack baggies for stratification. Here’s how I prepare them. I rarely get mold. When mold happens,its white mold and I’ve discovered its because the seeds themselves have rotted.
I pierce each baggie all over with a pin. I fill it with a bit of pre-moistened coco fibre (the kind that comes in blocks) and then I throw in the seeds. You can also use peat moss, but I find this product is easier to use. The quantity of cocofiber or peat moss depends on the quantity of seeds. You need enough so that there’s not too much contact with the plastic bag. I write cross info with a permanent marker on wide masking tape and affix it to baggie. I make sure its large enough so I can add germinations dates or any other info at a later date.
I put the baggies in an ordinary plastic bag & roll it up put it in the fridge until I need to check the seeds. If I discover that the cocofiber needs to be re-moistened, I use a hand sprayer to spray (water with some H202)only as much as needed. When you check for sprouts, all you have to do is tumble the seeds from side to side. They don’t stick to anything & they’re easy to remove either with your fingers or with tweezers. Bouncing them around doesn’t seem to hurt them. The sprouts are easy to see because they’re white.
Years ago, before I heard of the virtues of hydrogen peroxide, before plastic baggies were invented, I used to stratify seeds in peat moss in film canisters. Checking for sprouting was rather tedious, but I rarely encountered mold. I think there must be something in the properties of fibrous material that inhibits mold growth.
I only pot up seeds that have germinated & initially water with some peroxide in it.
Before planting seedlings that are germinating from moldy seeds, I soak them for a few minutes in H2O2 straight from the bottle. It seems to reduce the number of early seedlings deaths.
Sometimes seeds germinate but fail to develop. That is probably due to a genetic defect. It is more common with some parents than others.
Thanks both of you. I’ve been doing the quick soak before planting recently. Also, I just got a new batch of seeds and treated them with a serious cleaning AND a 24hr straight H2O2 soak. I do believe this was my problem. I’ll report back and let you know how it goes. Meanwhile, I’m curious - has anyone tried Neem Oil or Safer’s sulfur fungicide instead of Captan?