How To Grow Your Own Potatoes – Part II

An article by Travis Key from Lazy Dog Farm

Our last blog included many helpful tips to prepare for planting potatoes in your backyard garden. These included when to plant potatoes, choosing a potato variety based on maturity date, green sprouting potatoes, and whether to cut seed potatoes or plant whole potatoes. In this blog we’ll continue the potato discussion with planting and growing tips to maximize your harvest.

Preparing Your Soil for Planting Potatoes

Potatoes grow best in well-drained soil. I wouldn’t recommend planting potatoes in an area that stays saturated for days after a hard rain. Choose an area that drains well so the potatoes are not likely to rot from being in wet soil for too long.

It’s not a bad idea to get a soil test a month or so before planting potatoes. The soil test will provide the pH of your soil and let you know if there are any major nutrient deficiencies present. Potatoes prefer soil with a pH between 6.0 and 6.5.

I’m a big believer in crop rotation to minimize pest damage from one year to the next. Don’t plant potatoes in an area that has had any other nightshades grown there in the last year or two. Nightshades include tomatoes, peppers, eggplant, and potatoes.

How to Space Your Seed Potatoes

Our last blog discussed the benefits of cutting your seed potatoes into pieces that are approximately half the size of an egg. This will not only give you more “bang for your buck” with your seed potato investment, but it will also maximize your harvest. However, if your seed potatoes are small, just plant the whole thing.

Seed potato spacing will vary depending on whether you’re planting potatoes in an in-ground garden or a raised bed/container garden. For in-ground gardens, I recommend planting cut seed potato pieces every 6-8” along the row. If you’re planting whole potatoes, you might want to space them farther — something like 10-12”. Don’t worry about being super exact with this.

If you’re growing multiple rows of potatoes in an in-ground garden, I recommend giving at least 3’ of space between rows. This will allow room for hilling, which we’ll discuss below. It also makes it much more enjoyable to harvest the potatoes with room between the rows for a wheelbarrow or harvesting basket.

When growing potatoes in a container or raised bed garden, you can space them a little closer. I’d recommend giving each seed piece a 4-6” halo and planting them all throughout the container or raised bed. This will allow you to maximize your space and the eventual harvest you get. Just know that the closer you place the seed pieces, the smaller your potatoes might be.

Fertilizing Potato Plants

We like to use a somewhat balanced fertilizer for potatoes — something with relatively equal parts of N, P, & K. AgroThrive General Purpose works great on potatoes and is easy to apply by simply dissolving the fertilizer a 5-gallon bucket and pouring alongside the plants. If your soil test shows that your soils are deficient in potassium or phosphorous, you might consider using AgroThrive Fruit and Flower instead of the General Purpose formulation.

I usually fertilize potatoes 2-3 times throughout their 90-100 day growth cycle. Frequency will depend on the appearance of the plants. If the plants are robust and the leaves are dark green, I might only fertilize them twice. If the leaves are pale green and plants are not robust, I might give them an additional fertilization.

Start with a “soil drench” of AgroThrive General Purpose before planting potatoes. Mix 4-6 ounces in a 5 gallon bucket and pour along the intended planting area. This will ensure there are quality nutrients present when the seed potato pieces start forming roots and leaves.

Once the potato plants are a foot tall, fertilize them again with either AgroThrive General Purpose or AgroThrive Fruit and Flower. Mix 4-6 ounces in a 5-gallon bucket and pour alongside the plants. Try and pour slowly so you don’t erode the soil around the potato plants. If your potato plants continue to look green and healthy, another fertilization might not be necessary. But if the plants start to lose their dark green color as they grow, consider another feeding in a couple weeks.

Hilling Potato Plants as They Grow

“Hilling” is the process of adding soil to your potato plants as they grow. This helps to support the plant and encourage more potato development along the main stem. Hilling can be with a hoe, a rake, or just your hands on a small scale. If you’re growing in a container or raised bed, just add more soil to the container as they grow. This creates a hill around the plants and will help to maximize your harvests.

Some gardeners don’t have the softest soils, which can make hilling difficult. As a result, some backyard gardeners prefer to use straw or mulch to hill their plants. They’ll simply add more straw or mulch as the plants grow. I haven’t had much luck with this method, but I know many gardeners that swear by it.

When to Harvest Potatoes 

Potatoes will need to be harvested when they near their 90-100 day maturity date, or when the plants start to yellow and die. This is a natural process in the growth cycle of the potato. As the plants reach maturity, they start looking quite sickly. But don’t worry, this is supposed to happen.

To maximize potato size and storage potential, wait until the plants completely collapse and die. Then you can pull the plants and use your hands or a digging fork to gather your delicious homegrown potatoes from the soil. In softer soils you often don’t need any tools at all to dig potatoes.

The only exception for the harvesting guidelines above is if you’re getting a bunch of rain. If you’re expecting a significant amount of rainfall and your potato plants are already starting to die back some, you may want to harvest early. You don’t want your beautiful potatoes rotting in the ground because of too much moisture.

Storing Potatoes After Harvesting

Your harvested potatoes will be dirty, but that’s okay. DON’T WASH THEM! This is the biggest mistake we see with new gardeners growing potatoes for the first time. If you wash potatoes, it will dramatically reduce the storage potential. Don’t wash them until you’re ready to eat them.

Store your harvested potatoes in a cool, dark place that gets decent airflow. A basement or root cellar works well if you have one of those. We store ours on a rack of hardware cloth under our pole barn but use what you have. If you keep them cool and dry, you should be able to enjoy them for months to come!

Thousands of gardeners have been tuning in to The Lazy Dog Farm YouTube channel where Travis covers a variety topics ranging from how to successfully start seedlings to how to make a flavorful hotsauce that packs a punch. Accompanied by his wife Brooklyn and their two boys, the gardens on their 2 acre homestead in southwest Georgia are always filled with a wide variety of vegetables that are enjoyed fresh or preserved for later.