Planting Potatoes in Pots

What are we doing in the garden right now? A whole lot of stuff, but let's consider the humble potato.  We only grow fingerling types for Manresa.  They are tastier and more useful for the chef.  We can start harvesting them earlier than standard-type potatoes as well.

I buy my seed potatoes from Ronniger's in Colorado.  They are certified disease free, and that's important.  Potatoes, being in the nightshade family like their cousins tomatoes, peppers and eggplants, are disease-prone.  That's one of two reasons why it's not a good idea to take a sprouting spud out of your pantry and plant it in your garden.  The other reason is that potatoes purchased for consumption have often times been treated with an anti-sprouting agent.  Since you WANT your young potato tubers to sprout, this is not a good quality.  I like the price and the selection available from Ronniger's.

When the potatoes arrive, I cut up the larger ones (I know they tell you not to, but hear me out here).  When you look at a potato tuber, there are more eyes on one end.  Never noticed that before, did ya?  Well look at one next time, and you'll see I'm right.  So I always cut the tuber such that it's not exactly in half; the end with more eyes doesn't have to be as big as the end with less eyes, get it?  I will sometimes cut extra long fingerlings in thirds.  Small tubers don't get cut at all.

All the tubers get put in a single layer in seedling trays (open at the bottom for air flow).  I then put them in a warm, bright room.  The combo of the two gets the potatoes to pop their eyes out (or sprout slightly).  This process is called "chitting."  No giggles, now.  That takes a couple of weeks.  Since I put them in an open tray, and give them plenty of air space, the cut ends seal themselves.  If I had cut them and planted them immediately, I would run into some rotting issues.  That's the reason Ronniger's gives you instructions on not cutting the tubers before planting.  I guess they don't trust you to chit them properly.

I like to grow potatoes in 15 gallon pots.  That way, I don't have to mess up my planting beds when I harvest them.  I can also easily "earth them up" as they grow.  Earthing up is essential.  As the potato plant sprouts out of the ground and gets bigger, you need to add soil to promote tuber growth under the surface.  If you don't do this, then you get less tubers and risk the possibility of the tubers you do have being too close to the surface and photosynthesizing.  Green potatoes: bad!

First, we disinfect our stash of used pots with a mixture of one part bleach to 10 parts water.  This kills any over-wintering bacteria or viruses on the containers, and is a key step to keep them as disease-free as possible.  We also use brand new potting soil.  I like Sunland's Premium Grower's Mix.  This is sterile and doesn't risk imparting soil-borne bugga-boos into the potato pots.  Here's a pot being dunked and twirled in a disinfecting bath:

We then place only 4 inches of potting soil into the bottom of each pot. Lisette, our farm intern from UCSC, is on the job:
Once the soil is in the pots, we simply push five tubers into each one, about two inches under. That means there are two inches of soil below the tubers, and two inches above. The pots are then placed in our large unheated hoophouse and watered well. Although the ambient nighttime low temperatures inside the hoophouse aren't much greater than outside, the potatoes will be happier in there. Since it's late winter, we'll place a heavy frost blanket over the tops of the pots on nights that are forecasted to be frosty, and remove the blanket in the mornings. We'll water them perhaps once a week until they start to break the surface. When the plants reach about 8 inches tall, we'll add 6 or so inches of soil, water again, and let them grow. Another 8 inches or so of growth will trigger another 6 inches of soil added. This will be repeated until the potato plants are quite tall over the top of the container and the soil has reached the rim. They'll continue to need watering every week. When they flower, we can start harvesting.  We overturn a few pots every couple of days for the restaurant, dig through the pile of soil, and pull potatoes from the earth that are truly delicious.

These gorgeous Purple Peruvians were photographed freshly pulled last spring here at the farm. Courtesy Chezpim.

Comments

[Love Apple Farms]

Hi Pam: In Wisonsin, you shouldn't be planting out potatoes until mid May. Only use certified, disease-free potato tubers. Don't try to use potatoes you've purchased from a grocery store or super market. We like to buy our potato tubers from www.potatogarden.com

[Pam]

Hi...what an interesting site!

I'm in Wisconsin and looking at planting some fingerlings via your 15 gallon pot procedure. Any idea on when to plant these or even if they would be a good go out here?

Thanks a ton.

[Love Apple Farm]

Hi Sarah: I would not cut those, if the seed potatoes are egg sized. You want to chit them first, which is leaving them in a single layer in a warm, light-filled room until their eyes start to sprout. Then plant them.

[Sarah]

Love your post! I bought some seed potatoes today and am very excited to start our first potatoes with the kids. We plan to use our 15 gallon tree containers ( like yours ) my question is: did you drill holes on side or just rely on the drainage holes that are already there? Also, my seeds are very small - egg size. Would you cut those or plant whole? Thank you!!

[Krista]

July 12th in Santa Barbara and I'm going to do this! I wouldn't think it's "too late" here seeing as our local organic Island Seed & Feed store is selling the potato seeds. Now I'm going to look for that 15 gallon container. The info on 5 tubers per pot was exactly what I was looking for - thanks!

[Love Apple Farm]

No, it's not too late!

[Nancy]

Is June 19 to late to plant my second crop of potatoes in Western Washington?

[Love Apple Farm]

Katherine: You do not want to cut them and then just plant them. They should be allowed to callous over their cut before planting so as to prevent them rotting underground. Go ahead and cut them now before you leave. Place them all on a single level, and put them in the shade. Plant them when you get back.

[Katherine]

Great article! Very helpful-- I am sprouting some seed potatoes I bought from Seed Savers' Exchange, but will not be able to plant them as soon as I'd hoped (going out of town). I haven't cut them yet, but they do have green buds at the eyes. Do you think they'll rot in the two weeks that I'm gone, or is it safe to wait to plant them when I come back?

[Barbie S.]

Hi there, this is Barbie S. from March, my potatoes look awesome! I used a few from the store just to try them out to see what will happen and I also bought some seed potatoes. I kept them inside all nice and warm and put them outside when there wasn't any sign of frost. I just got done covering them with more dirt! Totally stoked! The next time I chime in with you I'll report how many I actually got out of the buckets. Thanks for your help!

[Sarah]

Thanks for your article. I've been researching growing my tubers in containers (I'm thinking the large bags of soil with drainage holes poked in the bottom). In all my research, I've seldom found posts that have the detail I was looking for. Thanks again!

[Love Apple Farm]

Karey: Once they sprout out of the soil, they need sunlight. Yes, I know that it's tough to have the sun get down inside the pot. They would love it if you were able to put the pot on something that tilted it south a bit. A long two by four perhaps on the ground? Or a brick? We don't do that here, but if I had all the time in the world, I would do that.

[Karey]

I just put the first potatoes in the 4" of soil and the other potatoes are chitting. At this early stage of continuing to add soil till they're at the top of the pot do they need any sunlight? Of course with the tall pot they'd only get a bit of overhead each day, but I put them out of the way for now in my greenhouse, so no sunlight will reach them. Is that ok till they're to the top and then set them out in the light?

[Cheryl Z]

Thanks for the informative article--for several years (10+) I have simply bought organic potatoes from our co-op, pre-sprouted them, and planted them on top of the garden, covered with well-rotted leaves/soil. Always get a great crop. Last year I got brave and cut some of the larger ones, letting them scab over before planting. This year, I'm doing the same, but as an experiment, with half of them, I'm planting each in it's own quart pot, and into the small portable greenhouse on our deck. Then I hope to transplant these potato plants into the garden. We're in Minnesota, and our raised garden is somewhat soggy in the spring. Hopefully I will see a difference in the "potted" plants. I figure I do this with tomatoes and peppers, why not potatoes? If I'm very careful with the root systems (I'm a pro violinist with very sensitive hands....) there shouldn't be a problem. Another idea is to "pot" them in heavy paper bags (on trays) and then plant the whole thing in the garden.

[Love Apple Farm]

Tina: Yes you can grow them in a pot, as well. You ultimately need about one cubic foot of soil for each tuber you plant.

[Tina]

Can I grow Kennebec in pots and if so how large of a pot would I need, Was thinking of building a graduated planter box that you add layers (height) to as you need to earth up

[Love Apple Farm]

Barbie: Go ahead and give it a try...can't hurt. Potatoes used from the supermarket are not certified disease-free, so it's a gamble using them. They're very disease-prone, just like other members of the nightshade family (tomatoes, peppers, eggplants). Let me know how it turns out!

[Barbie S.]

I'm in Indiana, I can start these pots inside right? Then take them out after the last frost? I hate to mention it, but I had potatoes in a bag growing already because I didn't use them fast enough. See any harm in trying those starts? I just used regular buckets with drill holes, think that will do also? This is the first time I'm trying potatoes. So if I get a few or its a loss it's okay. I've got five buckets followed everything you did and now I can't wait to see what happens.

[Joy Williams]

Any Idea where to get 15 gallon pots locally?

[Love Apple Farm]

Matt: It depends upon the season you plant them in, and the size of the mature potato you are hoping for. The fingerlings we planted on January 31 should be ready for us to begin to harvest (small sizes) around mid May. I can harvest a few pots at a time, and leave the rest for another six weeks.

[Matt]

Hi,
I was at your talk at the Eco-Farm conference.

How long until harvest?

[Love Apple Farm]

Joy: Yes, you do lose the plant. One shot at those potatoes!

[Joy Williams]

When you harvest the potatoes, do you totally lose the plants, or will it continue to grow for awhile. I'm trying to figure out how many pots I would need. ;)

[Annie]

Cynthia! I love this article. I've been wanting to plant my own potatoes but was completely clueless. And in pots too--that is the bomb! (As it'll free up my ground space for my precious tomatoes ^_^). Thank you very much.

[Carin]

This couldn't come at a better time I just ordered yukon golds and red ponitacs. I was wanting to do fingerlings as well but didn't know where to order them or to sure how to properly grow them. Every one I talk to gives different ways, I have heard stacking old tires, using hay/straw or just planting in a bag of soil. Next can you do one on carrots? I ordered some cool purple and other colors for my daughter but not sure the best way to plant them, container vs ground.