What Month Do You Plant Potatoes?: explaining when and why

There is nothing quite like the creamy texture of a homegrown potato. The difference in taste between homegrown and store-bought is so dramatic, that I try and grow most of my potatoes. What month I plant potatoes in is key to how many potatoes I can harvest.

Since potatoes store easily for the rest of the year, there is no reason why you can’t grow a year’s supply of potatoes. But knowing what month to plant potatoes will be essential to maximizing your growing season. Depending on where you live, you might even be able to take advantage of two harvests.

In this article I’ll tell you how to read the key signs to know when to plant your potatoes. This will help you make the most advantage of your growing season. I’ll also share some strategies on how to get two harvests from one garden bed. With these tips, you’ll be eating homegrown potatoes all year round.

What month do you plant potatoes 

The exact month to plant potatoes will vary a bit based on your seasons and climates. In most climates, you can start planting potatoes in March. In colder northern climates, mid-April is more realistic. In warmer climates, you can plant a fall crop in September or a winter crop in January or February.

In climates with freezing temperatures, look at the weather forecast to see when the last frost will be. From that point, you can grow immediately after that date or up to 2 weeks later.

Keep in mind that the last frost date is only a prediction. Unexpected drops in temperature it risky to plant potatoes right after the last frost. If you have the luxury of a long growing season, wait a week or two after the last frost to plant.

The Farmers Almanac has a useful tool on their website to help you find the right month to plant depending on your USDA zone. Simply type in your city or zip code in their planting calendar and you’ll get a cheat sheet on when to begin planting each crop.

What determines when you plant potatoes

What determines when you plant potatoes is soil temperature, humidity in the soil, and the length of your growing season. People with long growing seasons have a longer window for their plants to mature. While people with a short growing season must be efficient and precise with planting to fully take advantage.

The most important factor for planting potatoes is temperature. Potato plants won’t survive below freezing temperatures and optimal plant growth happens above 50 F. Finding the temperature of the soil is as easy as sticking a cooking thermometer into the ground. 

How much humidity is in the soil is also important. The soil should be dry enough that it doesn’t clump together when it’s wet. Seed potatoes are large masses of organic matter and they will rot in humid conditions.

Frost and excess rainfall will make the soil wet enough to cause your seed potatoes to rot. Avoid crop loss by planting potatoes in dry soil after fear of frost has passed.

The length of your growing season is the third important variable because it will determine how bold you must be. Shorter growing seasons mean you’ll have to plant potatoes out early even if it means risking a few to rot or cold. In warmer climates, you have the luxury of waiting until conditions are perfect to plant potatoes.

What is the minimum soil temperature needed to plant potatoes

Ideally, the minimum soil temperature needed to plant potatoes is 50 F. You can plant potatoes earlier, but will likely lose part of your crop to frost and excess humidity.

Optimal potato growth is also linked to temperature. So growing the most productive crop possible will depend on how you manage temperatures. Ideally, you’ll want to promote strong leaf growth at the beginning which will then sustain productive tuber development.

Potato roots will start growing in soils with temperatures over 50 F. However, optimal root growth will only happen when temperatures go above 59 F. Leaf growth and tuber development occurs at temperatures as low as 45 F. But like with roots, growth is stronger in temperatures above 65 F.

Planting as soon as soil temperatures reach 50 F is possible. But you’ll get the strongest, most productive growth in slightly warmer temperatures. Potato tubers grow best when soil temperature is about 75 F during the day and 50 to 55 F in the evening. 

Depending on the temperatures your potatoes grow in, you can expect some differences in tuber growth. In lower temperatures, you’ll get smaller potatoes. With warmer growing conditions, the plant will put out fewer tubers but the potatoes will be larger.

If I can, I always wait the extra couple of weeks for warmer temperatures. But I live in a 9b climate zone where the growing season is long. This allows me a week or so extra for a short crop or if I’m not using the bed, it’s less time watering.

What is double cropping

Double cropping refers to the practice of planting multiple rounds of crops within the same year. There are several strategies for double cropping which include planting complementary varieties (such as soybeans and corn) or multiple rounds of the same crop.

If you time it correctly and have a long enough growing season, do a double-cropping of potatoes. Because of the warmer temperatures in late summer the plants will get established and grow quickly. The second crop of potatoes will only need 3 months to grow before the frost sets in. 

To plant a second crop of potatoes, start by harvesting your first round to clear out the garden bed. This usually happens in early to mid July.  Then you would re-plant the bed again with a new round of seed potatoes.

We have a guide on how to grow potatoes, which will take you step by step through the potato planting process. The only thing I’d recommend is to replenish the soil with compost or aged manure. 

Potatoes are heavy feeders, so I usually add the compost directly into the bottom of the trench and use a hand shovel to work it in a bit. If you don’t have compost available look to the beach. Seaweed fertilizer is a great option for feeding potatoes and you can use it before and/or after planting.

Potatoes planted in late summer will need to be protected from the cold so I recommend mulching heavily. If temperatures drop unexpectedly early, harvest all the plants and enjoy fingerling-style potatoes. Keeping plants in the ground in cold temperatures will cause the tubers to get black spots or rot.

If your growing season isn’t long enough you can always do the second round of potatoes in containers. This way you can bring them inside as it gets cold. Harvesting potatoes right in your kitchen is a great conversation topic at dinner parties and they make beautiful houseplants.

Can all countries grow two crops of potatoes in one year

Not all countries can grow two crops of potatoes in one year outside. Growing two crops of potatoes is only possible if you have a long enough growing season to accommodate the overlap. Excess rain or extreme cold will destroy the second crop if it doesn’t have enough time to mature.

Even within the United States, you’ll experience very different growing conditions. Gardeners in Florida will have more in common with gardeners in tropical countries than with growers in upstate New York.

In countries that have a growing season over seven months, gardeners can grow two crops of potatoes in one year. Gardeners in the rest of the world can always plant a second round of potatoes indoorseven in a bucket!

Summary

Potatoes are an easy staple crop to grow in your garden. They are low maintenance, provide a huge yield in relation to space, and store well. All in all, a great crop for beginner gardeners.

If you want to take your potato growing game to the next level, you’ll need to know what month to plant your potatoes. Potatoes are usually planted in March, but depending on your USDA agricultural zone, this can vary.

Planting potatoes in the right month is important because factors like soil temperatures will greatly impact potato quality. Planting in the right month can also mean you have time to squeeze in a second crop of potatoes.

Now, who wouldn’t want to grow the most amount of potatoes possible? Once you’ve gotten used to homegrown potatoes, you’ll never want to buy them again.