Friday, July 10, 2015

Potato Harvest 2015

One of the things I got done over the July 4th weekend was harvest my potatoes. The tops had mostly died back, and it was getting hot out there, so it was time for them to come out.

Potatoes are difficult to grow in Central Texas. They don't like freezing temperatures, but they don't like hot temperatures either, so that leaves only a small window where they're comfortable in a Central Texas garden. They also prefer acidic soil, and my soil is around pH 7.5 - 8.0.

Therefore, for the past few years I've been on a learning curve figuring out the best way to grow them. I think I'm finally starting to get the hang of it, because this year they did well enough that I have plenty of potatoes for eating as well as saving some for replanting.

I planted six varieties of potatoes this year. Two of them, Red Pontiac and Purple Viking, are varieties I've been growing for several years now, and they continue to do well. I originally got them from Potato Garden. To try out some new varieties, I bought the Cook's Potato Mix from Southern Exposure Seed Exchange, which has one pound each of four varieties: Caribe, Cranberry Red, King Harry, and Rose Gold.

I planted Red Pontiac and Purple Viking on January 18. I'm still trying figure out how early is too early to plant potatoes. Most sources say I'm supposed to plant them around Valentines Day, but I have been trying to push that date earlier to make sure they have plenty of time to mature before it gets hot. If I plant them too early, they start to grow a lot, and then if we get another hard freeze, they can get badly damaged. That happened when I tried planting some in November 2013, which turned out to be way too early. Luckily I didn't plant all of them that early, so I could plant some more later in January of 2014 when the first planting froze to death.

Potatoes are heavy feeders, so another thing I tried this year was to really work the soil well and add a lot of goodies to make sure they had plenty of nutrients. I used a modified version of John Jeavons's double-digging method, but without the double part because my soil is too compacted and rocky down there. Basically I dug a trench out from the end of the raised bed, put that in a wheelbarrow, laid the seed potatoes down in the trench, sprinkled some organic fertilizer and compost on top, filled in the trench with soil from the next trench, and repeated the process until the whole bed was planted. The last trench was filled with soil from the first trench. Then I spread even more compost on top. The resulted in seed potatoes about 8-10 inches deep, with very loose fluffy soil with lots of organic matter covering them. It was a lot of physical work, but I think it turned out to be worth it.

One mistake I made was waiting until the potatoes had sprouted and grown a lot of leaves before mulching them thickly with hay. It was still pretty cold and damp when I did that, so pillbugs got under the hay and ate so many leaves off my Red Pontiac plants that they died. I would say about half of them died from that.

I received my seed potatoes from Southern Exposure Seed Exchange in early March, and planted them March 7. I treated them the exact same way as the Red Pontiac and Purple Vikings, except this time I put the thick hay mulch on top right away. That way, they didn't leaf out until their stems had grown up above the mulch, and the pillbugs didn't eat them.

All of the potatoes were harvested on July 2, and here are my results.

Red Pontiac and Purple Viking

Red Pontiac and Purple Viking
I planted 20 Red Pontiac plants and 16 Purple Viking plants and they all did great. The fertilizer must have helped, because I don't think I've ever gotten potatoes this big before. I got plenty to eat as well as save some for replanting next year. Even though the Red Pontiacs were damaged by the pillbugs, you can see I still got a respectable crop from them. I planted fewer Purple Vikings, but got the biggest yield from them.

I think Purple Viking is still my favorite potato variety. Red Pontiac doesn't always do as well, but one advantage is it's earlier than Purple Viking, so I'll keep growing both.

Now for the newbies from Southern Exposure Seed Exchange.

Caribe

Caribe
Here's the description SESE gives for Caribe: One of the earliest and prettiest potatoes you'll dig. Deep purple skin with snow white flesh. Can be quite large with good yields. Good for boiling, baking, and frying. Lovely as a new potato. Very early maturing.

Well, they turned out to be the ugliest of SESE's potatoes! They yielded the highest, but the tubers were all cracked and knobby and rough.

But I did some research online and found out it may not be all the potatoes' fault. We had a lot of rain in the spring and early summer, and this can cause some varieties of potatoes to grow this way if they get a deluge of rain while the the tubers are growing. The tubers end up taking up too much water too quickly and the outside of the tuber cracks.

I considered whether I should give this variety a second chance or discontinue it. I didn't really want to eat them because of all the deep cracks full of dirt. This variety might be too similar to Purple Viking to be worth keeping. They're both purple skinned and white fleshed, and PV has already proven itself worthy.

Finally, I decided I will use them in an experiment. I'm going to try fall-planting these for a winter harvest. I've read about how you can plant potatoes here in August or September to maybe get a harvest before our first freeze in November or December. It's cutting it close because you're trying to grow them in that small window between weather that's too hot and weather that's too cold, and sometimes potatoes planted in the hot weather of August rot, but since these tubers are messed up anyway, if they don't make it I won't be too upset about losing them.

It would be nice to get two crops of potatoes a year. I don't really have anywhere good to store potatoes over the summer. You're not supposed to store them in the fridge because that ruins the taste, so the only other place is to put them in my pantry, which is really too warm to store potatoes optimally. During the day when we're at work, the air conditioner is set to 82 degrees to save electricity. Potatoes are ideally stored at 50 degrees. There's nowhere in my house that's 50 degrees in the summer!

So I can't really use potatoes as a long-term storage like they do up north, and instead they're a seasonal treat to be eaten quickly before they sprout or rot. It would be nice to have a second harvest in December because that would be long after the summer-harvested potatoes are gone.


Cranberry Red


Cranberry Red
SESE Description: Considered the best of the red-skinned, red-fleshed varieties. Excellent for potato salad because of its low starch content. Smooth texture and high yields.

While harvesting the potatoes I accidentally cut one in half and noticed the flesh really only has a pink blush. I wouldn't really call it red. This is also the variety that gave me the smallest yields. Besides the cut one, the ones you see in the picture are all I got, and they appeared to all have come from only one plant.

But the potatoes I did get, especially that one in the foreground, were so pretty that I decided to keep all of them to try replanting next year. Why did that one plant do well while the others had nothing? If they had all done as well as that one plant, I would have gotten a lot. Maybe I can get them to do better next year.

King Harry

King Harry
SESE Description: A new firm-fleshed round white potato from Cornell University that holds its shape well when boiled. These early and productive plants have hairy leaves, thanks to a wild potato from Bolivia, which deter pests like the Colorado Potato beetle. Great for potato salads, boiling, sautes and soups.

Of all the new varieties I got from SESE to try this year, King Harry did the best. It's the only one I got enough of to eat some as well as save some for replanting. The potatoes I got where very nice-looking round potatoes with blemish-free smooth skin.

The plants were considerably more vigorous than all my other potato varieties (though I didn't notice the leaves being significantly hairier). It sent out long sprawling vines, flowered profusely, and then made two big handfuls of potato berries for me! It must be the genes from that wild Bolivian potato.

I kept the potato berries to save the true potato seeds from to try growing them in the future. I've tried growing true potato seed before from some "purple potato seeds" I got in a GardenWeb swap years ago, but they never got big tubers. Maybe since King Harry has already proven itself as a good potato variety in my garden, it's offspring will also be good.

Caribe is the only other variety that flowered this year, and it never set fruits, but it might have contributed pollen to the King Harry seeds. I hope so, because that would give even more genetic diversity. It would be interesting to grow these seeds out and see what I get.

Overall, King Harry is definitely a keeper!

Rose Gold

Rose Gold
SESE's Description: Rosy red skin with a creamy delicious deep yellow flesh. Dry flesh is perfect baked or steamed. Disease resistant.

Rose Gold was the second best of the new varieties. It's supposed to be very similar to Yukon Gold, but with with a rosy blush to the skin. It didn't give me enough to eat some, but I still kept the ones I got for replanting next year to try to increase. The tubers I did get looked very nice. I would like to have a yellow-fleshed potato in my collection.

Summary:

Purple Viking - still my favorite
Red Pontiac - still good
King Harry - the best new variety; definitely a keeper
Rose Gold - giving it a second chance
Cranberry Red - giving it a second chance
Caribe - replanting in August as an experiment

I now have several pounds of Purple Viking, Red Pontiac, and King Harry to eat. The other day I roasted some chicken thighs with some of the potatoes that got impaled by the digging fork during harvest, and they were delicious. I like to roast chicken thighs and potatoes sprinkled with herbs like rosemary and sage, and stir it a bit as it cooks to let the fat that melts out of the chicken coat the potatoes and get them all nice and crispy. Mmmm!

It may be my imagination, but homegrown potatoes do taste better than store bought. And they were grown with no pesticides!

The potatoes I plan on replanting go in the spare fridge in the garage. Storing potatoes in the fridge makes them convert some of their starch to sugar, which makes them taste weird, and that's why you don't want to store potatoes you want to eat in the fridge. But if you're going to plant them, then who cares what they taste like? Keeping them in the fridge will keep them from rotting before it's time to plant them again.

Planting them in late January seems to work well. I think I had to cover them with frost blankets a time or two, and I did have that pillbug problem, but I still got a lot of nice big potatoes after doing that.

I look forward to seeing how the varieties from SESE do when planted earlier. When I planted Red Pontiac and Purple Viking in January and the SESE varieties in March, I expected the earlier planting to be ready to harvest earlier than the later planting, but that turned out to not be the case. They were all ready to harvest at around the same time.

At first I thought that earlier planting made no difference, until I dug them up and found out the earlier planting had much bigger tubers. Ah ha! I've made a discovery! The vines die in late June or early July no matter how early they were planted, probably triggered by the hot weather. But if they are planted earlier, they have more time to grow larger tubers before hot weather. So there is an advantage of planting earlier, but not the one I thought it would be.