Saturday, July 18, 2015

Two Sisters

As many of you know, I grow my corn and squash together. The main reason for doing it this way is that squash takes up a lot of space. My yard is small at only 9000 sqft with two townhouses and shared by two families. As you can see from my raised bed set up, I don't leave much room for the walkway as large paths take up space too. But it means that I have to control that squash.

In addition to Waltham butternut, this year I'm trialing Upper Ground Sweet Potato squash and Thai Rai Kaw Tok. There won't be a really fair comparison between the two as I plant the corn in succession and I plant the squash when I plant the corn. If I wait longer to plant the squash it won't have as much time to produce and our growing season isn't the longest. If I plant earlier than the corn, the corn won't survive as it gets smothered. So The UGSPS is bigger as it was planted a bit over two weeks earlier than the Thai squash.

UGSPS already halfway up the corn stalk

I have noticed that the UGSPS is aggressive. Waltham butternut will try to climb the corn, but only sometimes. Often it will clamber up a little and then stop. It is a fast grower, but it can't compete with UGSPS. The UGSPS will climb straight up and send out multiple branches that grow very fast. And all the squash will try to escape their beds. So every day I tuck the ends back into the bed and break off tendrils of the squash that have wrapped around the corn, and push the plants back to the ground. This method of growing a Two Sisters bed is time consuming, but so worth it if you have little space. We love our corn. It is such a treat in the summer. And squash is a winter storage staple.

And can you see what the two stalks of corn have in common? Each of them are producing three ears of corn. Not that I expect to actually get those. Last year my corn mostly produced two each, and the second ear was pretty sad. Maybe with three, two will be good. I can hope.

So why the difference this year? In addition to trialing different varieties of squash I'm trialing mycorrhizal fungi. In the spring for the peas and lettuce I saw no difference in the plants at all probably because the soil was too cold. But here it seems to be helping. Most of the beds all got the fungi, but one bed I only put it on one side of the bed. The northwest side. Usually the corn gets taller and produces better on the southeast side. This is the side on which I'm getting the three ears. However in that one bed where only some got the fungi, the corn is a little taller on the northwest side. So it seems to be helping. BTW I'm also doing a trial of it in my sweet potatoes. I haven't noticed a difference in growth there, but now the bed is so over grown I can't tell which plants are which.

For both beds the real story will be in the harvests. Putting out seemingly extra ears of corn is only useful if they all grow and fill out and produce more. OK it would be just as useful to make the corn more nutritious, but I have no way of determining that, so production and taste will be the deciders.


  1. I will be curious to see how the UGSPS compares to the Thai squash when it comes to aggressive growth. Here the Thai squash rambles all over the fence around the edge of the garden. I can imagine it would ramble over the corn too if I grew it.

  2. Your corn is looking so good. I'm thinking that next year I will plant my squash a bit earlier than the corn - Two of my corn stalks have been brought down in the last couple of days & I'm thinking the squash vines may deterred whatever it is that is getting into the corn patch. And I can't wait to hear about the results of your experiment.

  3. We've used two sisters on the past but now out squash grows sr the foot of the sweet peas.

  4. I'm growing corn for the first time this year (well, I tried last year, but didn't go well). The corn is going well and I see some of the squash plants have grown up the plant with fruit hanging high up. Is the concern that the squash fruit will overwhelm the corn? Too late for me, but I'm just wondering why you push the squash back down to the ground rather than allow it to grow up the corn.

    1. The squash I grow is very vigorous. I think if I left it to its own devices it would totally overwhelm the corn and would shade it out too much. I know the squash can produce just fine under the corn, though I do cut down the corn as soon as the ears are harvested. Also I think after the corn dies, if the squash are high up the wind might be able to blow the whole structure down. Maybe not.

    2. OK, I was thinking about the "blow the whole structure down" bit - it's a risk for sure. Guess I'll see how it goes. Fingers crossed for now :)