My current garden area was originally a hog pen 7 years ago. I raised 15 hogs in there as it was just below the dam to a large 100 foot diameter pond next to my house. The dam has a small leak in it that runs through that area which I used to water the hogs from and created a large mud wallow from. When I built the pen I had expected to eventually use it as a garden after the hogs. After 9 months of hogs the ground appeared to be toxic to plant life in general... lol... It was a desolate wasteland for a couple years and then started to grow plants again.
When the area started growing plants I decided to try and set up a garden in there. I couldn't hardly get anything to grow there but grass, it turns out is was wayyy too wet for effectively gardening. I tried a few ways to reduce the amount of moisture but didn't have much luck. Finally three years ago I started actually plumbing in a drainage system and began to have some luck.
As of this year one of my original dreams with this garden was realized... The flowing water melts off the snow earlier and keeps the ground from freezing... Woohoo... I found myself actually able to start prepping the garden by the second week of January, that is just crazy.... I have had to do a bit more plumbing this year but overall it is doing quite well. The southern end of the garden is still covered in a good foot of snow but about half the northern end was melted off, and then I shoveled the rest off.
I decided to try and get my potatoes in and with the help of one of my sons got quite a bit of them in this last weekend. I put them reasonably deep and I figure worst case scenario I can add another 6 inches of mulch if they start peeking through to early, that or just lay some clear plastic over the rows.
I boxed my seed potatoes from last year placing some thick brown paper between each layer of potatoes. I did not realize that the corners of the boxes would allow in so much light, I got a crazy amount of growth on the potatoes, though thankfully not a single lost potato.
For planting the taters I started with a layer of about 3 to 4 inches of light clay/soil mixed on top of the soft garden soil. Then I laid in about 4 inches of black highly organic soil from the forest floor, I just raked off the needles etc and carefully gathered the dark black soil from just beneath. Then I covered the potatoes with about 4 inches of the same black forest soil. Then I covered that over with 6 to 8 inches of loose pine/fir needles and forest floor detritus.
Thus begins the 2020 garden... Well I also planted some garlic, shallots and Swiss Chard under some light mulch as well. Looking at maybe putting some peas under mulch soon as well as I found a dozen sprouted peas that I had apparently missed last fall, clearly they are able to get started even now. I also found about ten potatoes buried in my garden, even with the deep freezes we have they were in perfect condition just two or three inches under the soil. The potatoes are now on the back fence line under mulch, have to see how they do. It would appear that even in our extreme winters potatoes can effectively be kept in the ground over winter here.
Now to haul in soil for the rest of my soil boxes and top them off with some mulch to protect from the snow and wait until it is warm enough to plant.
Originally it looked like it does in the pics with the horses until I built the hog pen. I thought it was great as the ground still had moisture in it in July, I thought this would be great for a natural gardening area...
With snow still on the ground I fear you may have started too early. While potato's can, do and will grow well in cool soils, I wouldn't recommend planting them as early as you have from the conditions shown in your photos, they may rot before they get enough warmth to actually start growing. Here in my part of Alaska I sometimes can plant them in mid may, but most years nothing goes in the ground until Memorial Day weekend (End of May, if you aren't familiar with US holidays).
So it was probably a mistake to start potatoes so soon. I think my plan would be to protect against freezing. I once planted tomatoes too early and I kept them alive during some freezing temperatures but I had some tricks first.
The first thing I did was to get a couple of black garbage bags (probably 30 gallon or so) and I filled them 1/4-1/3 filled. I made certain that I got these started on a day with plenty of sunlight and the light on the black bags really warmed up the water. Those bags then slowly released heat over the night and I created a local warm spot that did not freeze.
Step two was to trap as much warmth as possible. I put a cheap plastic tarp over the tomato towers at night to trap in as much heat as possible. The temperatures dipped into the 20’s but the tomatoes survived just fine.
Perhaps you could concoct something similar for your potatoes.
I was thinking of laying a couple clear plastic sheets over the rows, that will trap the heat in. There is quite a bit of microbial heat as well a lot of heat during the day with the sun. When I planted my garlics/shallots and Swiss Chard the other day the soil was actually "warm" to the touch with the sun light on there and the layer of leaves insulating it.
As for freezing I have no worries there the potatoes are a minimum of 8 to 10 inches away from outside air temps, even if we dropped into the teens they safe at this point. Heck the potatoes that I missed last fall that I dug up working in the upper portion of the garden two weeks ago were still in perfect shape and they were only about 2 to 4 inches deep in the soil with no overlaying mulch. My concern was more along the lines "rotting" or or a much earlier harvest due to the early start. Most plants are timed by sunlight and temperature though, as long as the sunlight is increasing in length and it isn't too warm these potatoes should grow, theoretically and hopefully giving me a little bit longer growing season.
I have started potatoes as early as the last week of March before and had crazy harvests on those years with the extra growing time and being able to make use of the large quantities of rainfall and whatnot. I was hoping that I can get by a few weeks earlier this year. I was a little concerned about how much excess growth I would have on my potatoes in another 3 to 4 weeks as I had vines hanging a foot outside the corners of the sealed boxes.
I still have another 30 pounds of potatoes that I can plant out yet, if these don't do well it will be no great loss. I will also likely still buy another 30 to 40 pounds or so to plant later as well. Potatoes are a crazy fun garden plant for me, little to nothing to them and when they have a good year it is a real kick harvesting all of those.
I had a pretty dang good year last year on potatoes though not as good as some years in the past. Last my big push and success was zucchinis, squash and pumpkin which did so crazy well that I now have enough seed to plant just about my entire 40 acres in with it this year if I wanted... lol... I am going to try planting some in my forests and let them grow up the south sides of the trees.
My main push this year is going to be getting cucumbers to grow, I have little luck with those yet here, time to change that... I am also going to branch out into leeks for the first time. Great cold weather plants that will literally grow under the snow...
For me, planting date for potatoes is while the apple trees are flowering. Most winters, I have potato volunteers, that spend the winter outside, and then sprout when they feel like it in the spring. So your potatoes might do fine.
I am finding that my soil is actually reasonably warm, I was out planting yesterday and again it was warm to the touch as I was pushing my fingers into the soil to make holes for seed. It has been getting down into the low 20's each night but getting up into the low to mid 40's during the day. End of this week it is supposed to go back down to lows in the mid teens and highs in the upper 30's to low 40's.
I would note that the soil that I am gathering is from the forest floor and was warm and frost free in spite of the temps. I assume this is due to the break down of the organic materials in the soil producing heat. It seems to be great soil for keeping things somewhat warm in the ground in spite of cold weather, though with the latest forecast I saw it could potentially sprout some things a bit earlier than I may want. We seem to be looking at about two weeks of colder than normal temps, hopefully it will warm up after that.
I would imagine with that warmer soil my potatoes are probably growing out at a decent rate at the moment. I am headed into town on Wednesday to take the wife to a couple Dr's appointments and I will pick up enough plastic to cover the potato section of the garden, that will hold in heat and protect anything that makes it through the 8 inches of material to the surface to soon.
Since my original posts I have dug up another dozen or so potatoes that were missed last fall that overwintered just fine. I think I am going to try some fall/winter planting of potatoes this year for next year and see if I can get that to work.
The danger is not the potatoes themselves freezing but them losing their leaves to frost to many times and not having the energy to regrow. I would not set potatoes out before 4 weeks before the last expected frost date.
You make a comment about light getting in, light is NOT what causes potatoes to sprout, those potatoes have been kept much to warm by the look of them hence the sprouts. My seed potatoes have either not begun to sprout yet or have very short sprouts. I am still digging some of last years potatoes and they have not begun to sprout yet.
My very early potatoes are on the window ledges chitting right now, they will be planted out at the end of April around 4 weeks before last frost but they will be planted into polly tunnels, you can do the same with fleece and frost blankets. They are a type called Soilst specificaly for planting and harvesting early as "new" potatoes.
No prison can hold Chairface Chippendale. And on a totally different topic ... my stuff: