Potato Grow Guide

A staple crop for our “homestead”, potatoes are something we love growing. But it’s taken many years of trial and error to find varieties that grow well for us and that store well. We spent the past 3 seasons growing out a large variety of yellow fleshed and russet style, and have come to consensus on which potatoes are our favorites. But this post is all about how to grow them, so let’s dig in.

Early late June through early July is my favorite time of potato season. So, so tidy tufts of vegetation!

Seasonality and Timing

Potatoes, like many foods we eat, have seasons within seasons. There are early potatoes, mid season potatoes, and late season potatoes. You can grow a few of each and enjoy a succession of potatoes all summer long, or focus on storage potatoes for winter consumption, or stagger plantings a bit and use some in late summer while still yielding plenty for winter enjoyment.

I take a bit of an unconventional approach to potatoes in that I plant them ALL on the same day and generally don’t harvest them until right around my first fall frost. We do pull off some plants, inevitably, for dinners, starting in late July through the end of the season. However, I tend to do that with plants that have died back early (which I often attribute to disease and also means they aren’t actively growing more spuds so why not eat them now, right?).

We grow mostly mid- and late season potatoes here, so it makes a lot of sense to just let them ride it out and cure in the ground before lifting them.

Site Prep

Well-amended and well draining soil, ideally free of large rocks that will impede burgeoning tubers will yield the best crop. Potatoes like it slightly acidic too, just under a neutral pH. If you don’t know your soil’s pH, consider getting your soil texted at your local extension agency.

Chitting

Ever wondered what this business was all about? Chitting is the simple process of pre-sprouting tubers to speed up the germination process. It’s particularly useful if you suffer from wet soils in spring where the tubers might be prone to rotting, and is purported to hasten your yield by up to 2 weeks!

Apparently, in the US it’s called “greensprouting”. Who knew? Not me. I feel this is a pretty common British tactic, likely due to their very maritime, rainy weather. I’ve never been impeded by soggy spring rains for potato sprouting here. If you live with really saturated soils in spring, chitting might be something you should consider.

Johnny’s has a nice write up about it here.

Planting and Plant Spacing

Potatoes, like garlic and sweet potatoes and dahlia tubers and heck, even apple and other fruit varieties, are grown from clones. We use our saved potatoes from the previous season, as we do our garlic, to plant the next year’s crop. I select small to mid-sized potatoes (because we often have a large surplus in spring) for planting. I generally do not cut my seed potatoes in half, because excess. If you need to, and with ordered seed potatoes you might, you can cut a potato up into about a golf ball (1-1 1/2” size ball) and plant those. They are ideally cut the day before you plant and should have several eyes on them.

The more space you give later maturing potatoes, the better yields you’ll likely have. I should take this advice myself, and maybe I will this year. I tend to plant my potatoes about 9” apart and 30” between rows. It’s recommended you give potatoes anywhere between 12-18” between plants for highest yields. The larger the seed potato, the further apart you should plant them. Perhaps we plant fewer spuds but further apart and still yield a ridiculous bounty of produce.

I dig a 6-8” deep trench and fertilize the entire trench generously (about 1/4 cup for each 12” section). Trenches run parallel to our garden beds. I set a tape measure in the bed and place a potato every 12” (we’re pretending I’m doing it right and so you will too!). I gently replace some of the mounded soil to the trench and water regularly. I will continue to add more soil as the plants grow (more on this in a minute).

Because I don’t chit (pre-sprout) my potatoes, they usually take a few weeks to sprout. Some varieties naturally wake up sooner but we usually get 100% “germination”.

You can plant seed potatoes several weeks before your last frost — if they sprout and get hit by a late frost, they will re-sprout but if it happens many times, your overall yield will likely be negatively impacted.

Hilling

Hilling potatoes does a few things. First, it helps the plants grow strong roots. The first time you hill, you will pretty much bury the plant excepting the top few sets of leaves, just like you might bury your stout tomato seedling upon planting so it, too, will put out new roots along its stem.

As the plants grow taller (if planted in early May by early July they should look gorgeous), I continue to add soil back to the trench, eventually starting to mound around the base of the plants to help protect any shallow tubers that develop from being exposed to sunlight which turns them green and concentrates solanines which can be harmful (cut out any green skin before cooking with them).

Early June and growing by the minute, these are ready to be hilled up to the tippity top of their foliage. Also, this is a great time to inspect. for any Colorado potato beetle eggs or larvae.

The second and final hilling which is when you end up mounding it could be done with straw or leaf mulch too. This method might work better for weed suppression and to disrupt the thorny but sluggish Colorado potato beetle. We might try straw this summer, but we usually just rely on our soft and pillowy top few inches of compost to do the trick.

Fertilization

Unsurprisingly, this heavy producer loves a lot of fertilizer and well-draining soils. We rely on our fall topping of compost to prepare our beds, and then fertilize only once, at transplanting. If your soil seems to be lacking nutrition, doing a fish emulsion foliar feeding is a common practice for potatoes about once a month during the growing season. Be sure to apply on a dry evening or early morning so as to not burn the foliage.

Disease Pressure

Colorado potato beetle and early blight are two diseases we’ve faced with potatoes over the year. For blights and other fungal diseases, it seems to be correlated to certain varieties. For example, we no longer grow Yukon Golds here, despite their prominence in the grocery store because they seem excessively disease prone. We’ve replaced them with Baltic Rose and Huckleberry Gold, two great yellow potato alternatives.

These are Colorado potato beetle larvae (olrder larval stages) and their disgusting frass. They are easily removed into a soapy pail of water.

Colorado potato beetles, like Japanese beetles, overwinter in the soil and emerge in late Spring. Their one redeeming quality is that they are sloth-like. Despite flying they don’t fly away or pee on you when you grab them. Their eggs are easy to spot on the underside of leaves (unlike Japanese beetles, come to think of it, where the heck do they lay those eggs?), and their many larval stages are equally easy to spot, catch, and plunk into a pail of soapy water.

A consistent, daily effort to control them will go a LONG way for future seasons. We got behind on them in 2021, the year my dad was dying of cancer, and 2022 was brutal but we did daily beetle pickings and 2023 was much mellower.

Harvesting

As I’ve alluded to, I prefer to leave my mature potatoes in the beds until pretty late in the season. I’ll even wait until after our first (light) frost to harvest our potatoes. A light frost won’t damage potatoes that are growing under the soil. It’s never been an issue for me. But colder air, say below 27, I’d probably be rushing to pull them out. Potatoes — the actual tubers — cannot withstand a frost.

To harvest, use a spade and dig a deep hole around the outside perimeter of the foliage. Some potatoes will be harmed in this process. You’ll separate them out and eat them first. As expert of a gardener as I am, I spear more than half a dozen potatoes annually during harvest season.

Ideally, your foliage dies back and you wait several weeks before harvesting. If you’re nearing your first frost and they are still green, you might want to cut the foliage down to tell the tubers to toughen up (this is akin to topping tomatoes, I’d say).

The advantage to waiting to harvest is that this gives the tubers lots of time to harden their skin. Potatoes that are harvested early have more tender skin. Think a new potato: super enjoyable to work with in the kitchen but not strong enough to sit around for 6 months waiting for the turn under the santuko knife.

Storing

Potatoes do best in cool temperatures (35-50F) and high humidity (>90%). They are one of our staple crops for our damp root cellar, and fared relatively well this season even with the warmer temperatures overall in the damp root cellar. Now that it’s mid-April, this is usually the time when I take the remaining potatoe and put them into our basement refrigerator (not a great place for longterm storage because it’s not humid enough).

But you don’t need a damp root cellar in order to store them. Here is what the root cellar is doing: it’s dark, so there’s no sunlight to spark greening of the skin. It’s cool, which is another signal that it’s not time to grow. And it’s damp, so that they hold their water content.

You can try and use a cooler corner of your basement or garage for this (garage only in warmer climates). Use a bin or box and layer them with newspaper. Be sure there’s airflow too. Check on them often to be sure they are storing well. Some people will take older fridges and add a bucket of water inside them to increase the humidity and it can act like a damp root cellar.

There are numerous ways to try and store potatoes without a root cellar, though I do believe it takes a lot of the guesswork out of it. If you’ve stored potatoes in your basement or some other corner of your home, please comment and let us know your tricks!