These days, virus free potatoes come from tissue culture techniques. These are the first generation. The same thing is done with sweet potatoes. Some commercial garlic producers are evidently doing the same thing. I don't really understand the process, but they are able to get rid of the viruses by heat treating (I think that is the technique) in the lab.

I don't know how long these techniques have been used. Certainly potatoes were around and used a very long time before these techniques became available. How bad things might get and how much reduction in yield you would get over time I don't know. I have seen figures on the reduction of yield in Beauregard sweet potatoes a number of years after the variety was introduced. It was quite a bit.

In sweet potatoes, I have read that taking stem cuttings reduces the transmission of viruses.

Robert

It isn't the storage that makes for disease, unless it's too damp and things simply rot. It's the stuff in the soil that gives the disease(s), which the tubers get as they grow. A lot of commercial growers grow in the same fields, year after year, which multiplies any disease and the chance that the tubers will pick it up. If you start out with really healthy (NOT freshly manured!!), fertile soil, that hasn't been growing potatoes (or tomatoes, or eggplant, or any other solanum family member), in the past few years, and can rotate crops over a 3-5 year rotation, then you should have a pretty good chance of keeping diseases to a minimum. Storing clean tubers, after they have cured and dried out well, in a relatively dry place, that won't freeze nor get much over 40F over the course of the winter, should allow you to keep growing from your own seed potatoes for a number of years. But I would think that eventually, you would have to go back and get new seed potatoes, as and if production fell off. Growing the older varieties, which have been grown for generations under the same conditions you want to use, should improve your chances of keeping a healthy stock. You could use a staggered system of getting new potatoes, and try new varieties at the same time?

The primary reasons commercial producers have these issues is that they only grow one variety for maximum production in the same field over and over. Everything we know about growing healthy gardens tells us that is just plain dumb.

The best way to limit disease is to grow many varieties, keep the soil organically and rotate where we plant each species while avoiding planting similar species in the same place.

I have not tried to store potatoes yet but I applaud your wisdom in not listening to those who think we must use "modern" techniques when there have always been natural alternatives.

For about 7 years I stored my own fingerling seed and never had any reduction in quality, quantity or disease issues.
Before fall rain I dug the last of 1 or 2 100 ft beds that were grown for market and selected healthy, seed size spuds. I didn't wash them but brushed off any clods and put them in a wax box in the walk in for the winter.
Come May(ish) they came out of the fridge, greened up and went in the ground.
Whenever possible I try to rotate out solanaceae for 3 years in the same spot in the field.

Since then, i've moved and now grow in a wetter climate but will hopefully start saving seed again (if I ever get them in the ground).

Where do you folks store your potato seed to keep the right temp and humidity? If I put mine in the shed they would freeze and in the basement would be too warm. I am looking for ideas because shipping on new seed is too expensive.

If experience is any teacher, I am inclined to say that storing the potatoes you plan to sprout the next year in dirt is as good an idea as any. I have had bad luck with storing them in paper bags, dark cupboards, etc., due to the seed rotting. But I always seem to miss a potato or two in the garden, and they sprout back up the next spring. So, my experiment this year is as follows: Dig up the potatoes. Fill a bucket with soil. Bury whole potato "seeds" in this soil. Keep the bucket in my basement, where there is no heat, other than indirect heat. Dump my bucket into the garden in spring, after consistent 45 degree temps. Wait and see.
Or, I could just give them a spot in the garden now, which is not desirable, as I recondition the soil, every year. But, these potatoes, don't seem to care, LOL!