Thursday, October 13, 2016

A potato experiment

Last spring, I didn't plant any potatoes in our garden. Why? Because I had so many volunteers coming up that I figured I'd devote the beds I might otherwise have used for potatoes to other plants instead.

Volunteer plants, as you doubtless know, are plants which grow spontaneously from seed left from the previous fall. Last year, when I dug potatoes, I'm sure some of the little marble-sized tubers got left behind as not worth bothering with. It is evidently these little rejects which grew all over the place.

Here's a big lush potato plant among the onions.

I also had potatoes among the cayenne peppers, broccoli, Brussels sprouts, carrots, etc.

I had no idea how these volunteers would produce, of course, but as summer waned into fall and I started digging up the results, I made a rather astonishing discovery: the potatoes were beautiful. The average size was much bigger than last year's harvest (which, admittedly, I planted late).

This got me wondering: why would the volunteer potatoes be so large, but the "properly" planted potatoes be small-to-medium? What made the difference?

The only thing I could think of is the volunteer potatoes overwintered in the ground. Around here, people are urged to plant potatoes early, April or May (depending on weather and snowpack), but so far as I know, no one recommends planting potatoes in the fall.

But what if? What if overwintering seed potatoes in the ground actually gave them a jump-start on early spring growth? What if planting potatoes in the fall produced a superior crop?

So, being the experimental person that I am, I decided to plant potatoes in the fall and see what happens.

I selected a bunch of small tubers, since presumably these are similar in size to what got left behind last year. (The scale is hard to tell in this photo, but the biggest ones are perhaps three inches across and the smallest ones are about the size of a large marble.)

I cleaned out eight beds...

... and put 15 little potatoes per bed. I buried them about 4 or 5 inches deep.

Then I mulched each bed with pine needle mulch.

Will this experiment work? I don't know; but if it fails, it's no big deal. I'm only out a few small potatoes and a little bit of effort.

But if it does work, well by golly we'll have found out something new. And that's kind of the fun part about gardening, don't you think?


  1. How many tires do you have? I think you've said this before, but ... well, I forgot :) Also, are they all the nylon-belted tractor kind? Those are easy enough to cut, but I haven't found a good way to cut steel-belted tires; if you have a secret, I'd love to know it.

    As an aside, you weren't perchance driving through Bonner's Ferry in a large pickup a couple weeks ago, were you? I was walking through with a noticeably large flock of children, and someone drove past who looked just like your blog picture.

    1. We have about 85 tractor-sized tires and another 25 or so large truck tires currently in use. We estimate we have room for another 150 large tractor tires, and over time we're putting these in place.

      The secret to cutting tires is to ONLY cut out the sidewalls, which don't appear to have steel belts in them (or at least, we haven't had any problem). We use a regular Saws-All for cutting, and only cut out one sidewall, leaving the other for support.

      Nope, that wasn't me in Bonner's Ferry. Haven't been there in years.

      - Patrice

    2. Hrm... I ran into steel all over the place, when I was cutting our first batch of 10 or 20, last spring. The poor Saws-All went through several blades, and shook me around enough that I got nasty headaches from it, a few different times. "Fortunately", we're stuck finding a good way to water the tires we've got, so I may not need to cut more for a while.

    3. Cut down into the sidewall from the side of the tire. If you attempt to cut up into the sidewall from where the tire meets the rim you WILL hit steel and just want to kill yourself before you get through it.

      Also, I've found a circular saw actually works really well for cutting sidewalls. It produces a bit less neat of a cut than the recip saw, but I find it easier on ME to use.

  2. I am doing the same experiment this year. I have saved the small marble potatoes and a few slightly larger ones to plant. I am hoping they will do better than what I have planted in spring for several years now. We eat a lot of potatoes and I have not had a decent crop yet.

  3. In past years I have not gotten to dig a row of potatoes and left them in the ground over the winter. They grew great the next year. Also, I have dug potatoes as late as Christmas and the potatoes were not rotten. Once we get a hard freeze though, all bets are off.

  4. Great idea! Maybe it's just like the garlic? You can plant garlic in the spring/early summer and then harvest in the fall but they are small and not very tasty, or so I am led to believe since I haven't bothered to do this. I always plant in Oct/Nov here in MA and harvest the first week in July, depending on the 'skins'. I am very interested to see how this turns out!!!

    God Bless,
    Janet in MA

  5. Most of this years potatoes were from overwintering. They tasted fine in the Spring too. One thing is if you replant small potatoes you'll be more likely to get smaller potatoes. Darwin and all.

  6. Did a little reading on this. They say dig ditch about ten inches deep, put three inch layer of mulch (dry leaves, grass clippings or unfinished compost). Plant your potatoes and then another layer of mulch. The about five inches of soil. If in real cold climate cover with leaves. In my case may use some pine needles to lower the PH, from 7, as spuds like 6 or lower. If it dries up a little after this rain spell will give it a try. Good luck on you attempt.

  7. Mrs. Lewis
    Check Backwoods Home magazine #48. nov/dec 1997.

  8. Yes, one of my favorite things about gardening (other than the food and my grocery budget and the exercise and...) is the permanent biology laboratory. I enjoy the mystery and discovery.

    I have one this summer I've not solved. I was very lazy and did not rotate my tomatoes. Out of 18 plants, 4 thrived, 4 died and had no root system when pulled out, and the remaining 10 languished. I wrote it down to soil parasites from failure to rotate and planned to take that bed out of service to correct the problem next year...

    ...and then along about September, the languishing plants took off prolifically.

    I watered them all equally (at least, until I gave up on the languishing plants early in August) and fertilized them all the same: compost dug into the soil, a handful of TomatoTone at when they were set out, top-dressed with compost mid to late June. I'm in western PA; our summer was somewhat dry and unusually hot.

    Any clue what happened with my 'maters?? It wasn't an issue this summer (had a heavy, late crop last year and canned like a madwoman), but curiosity is driving me mad and I would like to identify the problem so it can be corrected if it recurs.

  9. potatoes, we are told, should be planted in different ground every year to avoid disease.
    for what it's worth.

  10. I've followed your blog for a while and seen your "tire garden" in many posts. I'm curious though, are you ever worried about soil contamination from the petroleum in the tires?

    -Blind Ambition

    1. No, I'm not worried at all. The "poisonous" nature of tires for planting is, as it turns out, very much an urban myth. Please read this post for further explanation:

      - Patrice