Hi all; I was wondering about storing seeds that are not quite dry yet...I have some big fat nasturtium seeds that fell off the plant, but they are not brown yet. Are they going to be any good if I dry them in the house instead of on the plant? I also heard somewhere that there is a household product that can be used to absorb moisture for a use like this. It seems to me that it may take a while for them to turn brown, and I wanted to store them in a paper envelope with dessicant... Any help is appreciated! Thanks, Pat.
One homemade dessicant is dry milk, but only use when the seeds are completely dry, it is to help keep them dry. I am not to familiar with nasturtium seeds. Although most seeds need to be brown when harvasted, to be mature.
I wouldn't store them (dessicant or not) until they are dry. Leave them exposed on a paper plate for a week or two. Nasturtiums have a tan cork-like coating around the seeds. Make sure they're good and dry before you package them or you'll end up with mold. I made little packets of silica gel to toss in amongst the seed packs in my seed box. I think I also read that natural untreated kitty litter is a good substitute.
Craft stores sell half-pound jars of powdered silica gel for drying flowers. Or you can buy indosutrial-strength "Drierite" online.
But you actually don't want to reduce seed moisture below 3-5%. They're alive, and die if totally dessicated.
But be sure to get the mositure below 8% before freezeing them, or they'll rupture from the ice crystals!
I'm not sure what relative humidity is best for multi-year storage at room temperature or "cool", but I aim for around 10%.
Living in a damp climate, I have seen paper absorb humidity in my living room, and then raise the humidity inside a sealed jar to 20-30%, exhausting the first batch of desicant I put in with them.
Since plastic (polyethylene) actually DOES allow some water vapor to pass slowly through it, I don't worry about storing DRY seeds in plastic. And that "Zip-Lok zipper" can't possibly be a vapor-tight seal. At least plastic doesn't absorb water and then hold it right against the seeds!
I recently saw two suggestions I really liked.
If you don't have a "humidity indicator card", include a few strips of newsprint in the jar. next time you open the jar, feel the newsprint. If the dessicant is working and humidity is low, the paper will be stiff enoguh to crackle and crinkle. If it is even a little limp, you need new dessicant.
Those indicator cards are cheap, but I don't know where to get a small order without a large shipping charge. Now I wish I had bougth a dozen from Drierite, instead of just 3-4 (40 cents each!).
Flower-drying silca gel is so finely powdered that it sifts right through organza. But some website about peppers or tomatoes pointed out that you can put a few tsp of silica gel inside a coin envelope. Humidity can migrate through paper. They suggested closing it with a paperclip, but I used two staples.
Maybe there are fabrics fine enough to hold the powdered drying crystals inside, and still pass humidity faster than Kraft paper. But that would require sewing ... quite beyond my coordination.