The Extreme Gardener

Experiments in permaculture and
other gardening adventures in northeastern Vermont

Posts tagged ‘potatoes’

TPS Potatoes: Who’s Yer Daddy?

Monday, December 20th, 2010

I previously posted about two potato varieties grown in 1994 from TPS (true potato seed) I collected from a potato called Blue Shetland (SSE 1184). I am fascinated by Shetland potatoes, which come from the Islands of Shetland, off the Scottish coast. They are colorful inside and out, and their rich flavor is superior as far as I’m concerned, though folks who are used to the usual insipid tasting commercial potato varieties might find the flavor “strong”. My Shetland spuds tend to be small, but the flavor makes up for the size. They also keep very well.

Hurley's Purple Gold potatoes

Hurley’s Purple Gold, the mother plant. It very closely resembles its mother, Blue Shetland.

One of my two Blue Shetland offsprings, Hurley’s Purple Gold, very closely resembles its parent, and I was fortunate enough to collect a viable seed ball from it in 1996. But, after my initial experience growing potatoes from TPS, I was a bit leary of the time and space required, at least the way I went about it the first time. However, last winter I was inspired to try it again by the videos of Tom Wagner’s TPS workshop at Bifurcated Carrots.

Tom has a genius growing method for TPS that speeds up the process, and requires very little space. I don’t have a greenhouse, so all my seedlings are started on windowsills, which makes me very picky about starting seedlings early. Initially, I was going to get some TPS from Tom but I came across the old seed from Hurley’s Purple Gold and decided to go with that.

seedlings from true potato seed

All the seeds went into a little 2″ pot; about 30 germinated; emergent seedlings were exposed to direct outdoor sunlight; and later the eight strongest seedlings were transplanted to a 4″ pot, buried up to their top leaves. The close planting keeps the seedlings leggy, which is desirable in this case. The idea is to have long stems, since the tubers form on buried stems.

This method is so cool – I could easily see and compare color variations in the seedlings very early on (I’m looking and selecting for strong color), and the individual seedlings’ vigor is also quite apparent when they are grown in such competitive conditions. You can rogue out weaklings early on, and not waste energy and space with them.

TPS seedlings in the garden bed

As you can see, I spaced them rather closely in the garden bed. In hindsight, I wish I had given them more room – after my first TPS growout many years ago, I was not expecting full sized plants in the first year. I heaped compost on the plants several times during the growing season, burying as much stem as possible. This is how the plants looked just before I cut them down.

Purple Gold potatoes

Late blight struck the gardens about the second week of September 2010, so I cut all the foliage off at ground level much sooner than I normally would have. It was somewhat tempting to leave them to see how much late blight resistance they had, but I have no more TPS from the Shetland potatoes (they rarely set seed) so I really didn’t want to risk losing them. When I cut them, there was no sign of late blight on them. All our other potatoes had had their normal end of season foliage die-back, but these were still going strong. I assume that’s because they were first year seedlings, and not because they’re all very late maturing.

Digging up the spuds

Here’s an overview of the harvest. For me, digging up seedling potatoes feels like being a young child on Christmas morning. The TPS I used was not hand pollinated, so I didn’t really know what to expect. I grew about 8 other non-Shetland potato varieties the year I got the seed ball. I was hoping for more Shetland-y spuds, with darker yellow flesh, bigger tubers and red and purple skins. Initially when I dug them up, I was a little disappointed not to get more strong yellow flesh. I couldn’t really see the flesh colors very well, because I didn’t have time to cut into them, do photos and maybe cook some up. I just knicked the skin of one each to get a rough idea, and tucked them away until I could evaluate them better.

So, finally, here’s what what I got when I properly opened my presents, and I’m not disappointed any more.

Tuber portraits

#4 and Fenton

#4 left, Fenton (probable parent), right

One seedling (#4) was a monster, producing 5# of spuds, some of which weighed 10oz. We haven’t yet taste tested #4, but so far I am very impressed, and I like the really dark skin and flesh color. My guess is that the father was Fenton, an heirloom potato from Mercer ME I got from Will Bonsall via Seed Saver’s Exchange. Fenton’s one of those Congo, All-Blue, etc. blue/blue potatoes, and it’s a variety that we’ve kept over the years because it’s very rugged, productive, blooms profusely, and tastes really good – a nice baking potato. The other parental possibility would be Peruvian Purple, but I think it’s more likely Fenton.

#4 and Fenton

#5 right and parent Blossom, left

The other real stand-out was #5, which obviously was a cross with Blossom. Blossom was bred in Minnesota by Ewald Eliason with an eye for flowering, among other things, and is mentioned in Carol Deppe’s book Breed Your Own Vegetable Varieties. Blossom is a beautiful plant and has very good tasting all purpose pink fleshed potatoes. It’s also very rugged, another of our “old reliable” varieties. Blossom does bloom fairly strongly here, but I have never gotten a viable seed ball from it, whereas Fenton is a more reliable seed producer.

Anyway, #5 is REALLY tasty, and I like the strong red flesh color. The seedling made over 3# of tubers, a very respectable showing, I think. All in all, I’m pretty excited about this venture, though I think I will wait another year before I grow out more TPS, so that I can be sure to give the 2011 growout of 2010′s seedlings its due.

If you’re interested in Shetland potatoes and other TPS projects, Rebsie at Daughter of the Soil has a great post about the Shetland potatoes she’s working with.

Two sibling potatoes from seed

Thursday, November 13th, 2008

In 1994, I grew out some true seed taken from Blue Shetland potatoes in our garden. Of the 24 seedlings, we selected six to grow a second season, and of those six, we have kept two over the years.

The Blue Shetlands, the parent, came originally from Will Bonsal in Maine via the Seed Saver’s Exchange, and have dark violet skin, yellow flesh, and a tendency to have a violet ring. Seed was collected from the plants in 1987. Blue Shetlands have some of what I call “primitive” potato characteristics, compared to the modern potato varieties most people grow. The more primitive potatoes tend to have smaller tubers, the leaves are a bit smaller in proportion to the stalks, and eyes deeper. They also may send the tubers out through the soil further away from the above ground part of the plant, so finding them all can be a challenge, especially the dark blue skinned types.

So, here’s our Purple Gold, a bit lighter and redder skinned than the parent’s dark violet, but the same yellow flesh, and tendency to have a purple ring.

Purple Gold potatoesPurple Gold potato foliage

…and Rose Gold, a reddish version. I love the rose star in the flesh. They both have that rich yellow-flesh potato flavor – our favorite for skillet fries and potato salad.

Rose Gold potatoesRose Gold potato foliage

If you do grow potatoes from true seed, when you judge the offspring, first look for culinary characteristics that you like, even if the tubers are smaller than you want. It can take a few seasons of growing out for a potato variety to really show its full potential for tuber size and yield.