What is the Best weather to sow seed to reduce mold?

[Richard Hole]

Hello

It is spring and I am about to sow some Drosera seeds. I am growing them in a greenhouse with plastic on the sides and roof that stops the direct sun and rain entering. The white plastic blocks out 50% of the sun. The greenhouse is well ventilated. Do the weather conditions that follow in the week after the seeds are sown make much difference to the germination rate? The forecast for the rest of this week is rain and dark and overcast conditions with temperatures around 20 degrees Celsius. This is unseasonable for this time of the year as normally it is very sunny and about 30 degrees in the day time with humidity levels often around 30 to 60 percent. I thought that I would have more chance of mold growing on the surface of the soil if I sow my seeds now before the spell of humid overcast weather. However, if I wait for a week or two until the forecast is for warmer drier weather it may reduce the chance of mold.

I have made up the trays with peat moss in them to sow the seeds and I have them sitting in trays of water. We laid the peat in the seed boxes about a week back. Is that a disadvantage over having it just freshly dampened and put on the surface before the seeds are sown? I thought if it is left for a few days some algae or fungi may be starting to grow before I sow the seed. I could easily add a layer of fresh peat on the top a few millimeters thick just before I sow the seeds if that is an advantage.

Also, it may help to either boil or put the peat moss (that goes in the very top layer) in an oven to kill algae and fungi spores. The TEEM brand peat is dry in the bag but it may reduce the amount of algae and fungi if I boil or bake what I put on the surface. If you think this is an advantage, would I only need to do it for a new batch of peat that I could add to the top of the seed trays? It could also pay to wash the peat that goes on the surface well as discussed on earlier threads. However, it would be much easier if we only had to wash and boil the peat that goes on the top 5 millimeters. A smaller volume of peat could be washed more thoroughly and quickly.

The reason I thought about the above is that I had problems with mold before.

The species I plan to grow are Drosera:
Nidiformis, Slackii, Aliciae, dielsiana, Indica, Burmanii, and Capensis

Are some seasons better than others for sowing these seeds?

Your help is appreciated
Regards Richard.

[arvin555]

Richard, in my limited experience the biggest factor that affects mold growth for me is air circulation.

Example:

1. I sow some seeds on a pot and put a plastic cover that will keep moisture and slightly reduce sunlight, but it's a bit airtight. I usually get molds on those pots.

2. I sow some seeds in a pot and a plastic cover with some holes cut at the sides, molds usually are less likely to grow.

3. I sow some seeds in a pot and put the pot in an aquarium turned to the side, and usually these also don't get much molds.

So in my opinion as long as your greenhouse is covered and does not allow rain to get to your pots then should be okay, slightly overcast is actually nice for seed germination as well.

What I usually get is white weblike molds.

TTFN
Arvin

[Richard Hole]

Hello

Thanks for the suggestions.

I saw an article at http://www.colostate.edu/Dept/CoopEx...il/sterile.htm about how to sterilize soil. Please let me know what you think.

I thought an alternative could be to put some peat moss in a pot of water and then heat the water to 200° F so that the water remains above 180° F for 30 minutes. It may have to be kept on the stove to keep it to these temperatures. Do you think that could be better than putting it in an oven? Some other articles suggest to boil the peat moss. You can see them by doing a search for ‘boil peat’ on Google. I thought using hot water may be easier and reduce the chances of contaminating the oven. Also hot water would distribute heat more evenly.

Your help would be appreciated
Regards Richard.

[jimmy0123]

Can i just sow in an uncover pot with sphagnum moss under a shade? Will the seeds get blown away by wind and should i just sprinkle the seeds on top of the moss or should i cover with a bit of moss? About sterilize the soil i have thought of that before to kill the harmful microorganism but afraid it will also kill the good one as well (for crop plants not sure about CP though )

[arvin555]

Well yes! Actually a local CPer friend of mine does sterilize his seedling mix. I have actually tried it myself and yes as far as I know, those that I pour boiling water on or microwave does seem to be more resistant to molds and algae. Though I think that at the least what it does is kill possible seeds of weeds from the mix, which tended to grow and compete against my CP seedlings. I imagined that even after sterilization of the potting mix, because I keep the seedling pot or container outside at my Garden, I am sure that mold spore and the likes should still find their way onto the soil mix anyway. So I think that air circulation still is a bigger factor, unless you will cover the pot to avoid mold spores getting in.

Jimmy, the suggestion is to not cover the seeds. I don't think they can be blown away easily, if they do get blown off, if it's nepenthes then they are too dry in the first place.

I have another suggestion, which I also do with some of my seedlings. After sowing the seeds, I use some kind of a humidity dome, then once the seeds sprouted, you can start taking off the dome or cover, this will prevent the high humidity/high temperature environment that molds like.

TTFN
Arvin