Some vegetables can be planted in the fall to safely overwinter and give you an earlier crop than their spring-grown cousins; and early harvests are a huge bonus in the vegetable garden where they help to fill in the ‘hungry gap’.
The hungry gap is the time of year when last year’s harvest is all used up and this year’s crops are just being planted. And because potatoes are such a valuable source of calories, we want to have that first crop ready for harvest as soon as we possibly can.
So, can you plant potatoes in November to get that early harvest?
Unfortunately, the answer is no.
In this article, I’ll explain why you can’t plant potatoes outdoors in November in the Northern Hemisphere, and when you should plant them instead.
Can You Plant Potatoes In November?
As I already mentioned above, you can’t plant your potatoes outdoors in November. The simple reason for this, is that potatoes can’t survive a hard frost.
Some vegetables like kale, Swiss chard, (some) peas, broad/fava beans, and leeks, will all shrug off a frost. With these plants you can have fresh veggies to pick over winter, and the peas and broad beans will sit as young plants establishing their root network, ready to explode into growth as soon as spring gets going.
But potatoes in leaf will die if they’re exposed to a hard frost late in the season.
Michigan State University reports that solanaceous plants (which include potatoes) are easily damaged by a light frost, at temperatures between 28 and 32 degrees Fahrenheit (-2 – 0 degrees Celsius).
So even though it would be great if we could have potatoes already established and ready to grow at the first sign of spring, there isn’t any way to get that to happen when you’re growing outdoors.
But because potatoes keep fairly well once harvested, you can grow a crop for an early winter harvest, and that should see you through until your first early potatoes are ready the following year.
When To Plant Potatoes For A Winter Harvest
Your growing zone will determine the last practical potato planting date for your location. Remember, potato plants need time to grow, flower, and develop tubers before the first hard frosts kill off the plant above ground level.
Find your growing zone using the USDA Growing Zone Map. It’s interactive, and all you need to do is click on your area on the map, and you’ll get a popup box with your growing zone info. Use the scroll on your mouse to zoom in on the map and pinpoint your location more precisely.
If you live in the UK, you can find your planting zone information at plantmaps.com.
Once you know your zone, you need to find your last frost date. The easiest way to find that information is to head over to frostdate.com.
From the menu, click on your zone to see your dates.
So, for example if you lived in Columbus, Ohio which is USDA zone 6a, your frost dates would be:
- Last Spring Frost – April 15
- First Fall Frost – October 15
Then you can look a little further down the page, and choose potatoes from the list. When you click, you’ll see a chart showing when you can plant. For zone 6a the last certain planting date is September.
Know The Days-To-Maturity Of Your Potato Variety
One thing to keep in mind, is the days-to-maturity of the particular potato you plan to grow. Early types will be ready for harvest in 90 days or less, while maincrop can take 110 days.
Early potatoes don’t store well for as long as maincrop varieties, so factor that in when you decide which types to grow.
To harvest a maincrop variety of potato later in the year, count back 110 days from your first frost date, to get the latest date you should plant.
Whichever type of potato you plant, get your potatoes off to a faster start by chitting them first.
Chit potatoes by exposing them to indirect sunlight, for a 3 or 4 weeks indoors. The eyes on the potatoes will sprout short green stubby growths which are the chits.
You may be wondering how you can plant potatoes at the beginning of September in Ohio, when the first frost is only 6 weeks (42 days) away, because that’s not enough time for the 90 or 110 days the crop needs.
Well, the first frosts of the season are usually light and of short duration, and while they won’t survive a hard freeze, potatoes can survive a light, short one. For increased cold endurance, you can give your plants some frost protection.
How To Protect Potato Plants From frost
To give your potato plants extra protection against frost, use floating row covers made with horticultural fleece. Fleece still lets light through and it will keep frost off the leaves of your potato plants, and increase the temperature by a few degrees depending on the weight of the fleece.
If you’re planting in the spring, you can cover small plants with straw instead if you have it – (the amount you would need for large plants in the fall would make it a nuisance to store unless you have lots of space).
I’m writing this on April 1st and my last frost date was mid March, and wouldn’t you know it, we’ve got frost forecast, and we even had a light flurry of snow yesterday. My potatoes which emerged last week are waiting it out under heaps of dry bracken.
You’ll need to keep an eye on the weather forecast and if a frost is predicted, make sure you cover your rows.
Keep in mind that the first frost date is just an average though, you still might not see a frost for several weeks.
When To Plant First Early Potatoes
Finding the date for your first early potatoes follows the same process that we just used above.
Find your zone information, then check the last frost date.
As a general rule of thumb, you can plant your seed potato 2 – 4 weeks BEFORE the last frost date. Potatoes take a few weeks to emerge from the soil, so killing frosts should be over by the time your plants come up.
It’s also a good idea to check your soil temperature with a soil thermometer prior to planting your potatoes. Soil temps should have warmed up to at least 50 degrees Fahrenheit (10 degrees Celsius).
You can increase soil temperature by covering your potato beds with black plastic a few weeks before your last frost date – just remember to remove the plastic so the potato plants can get light when they emerge. Every little bit of extra warmth you can give your plants early in the growing season, will help them get off to a good start.
Potatoes can’t be grown over winter outdoors because they will die off once the cold weather arrives. You can’t plant potatoes in November, but you can plant potatoes in the fall to harvest in November or December.