Potatoes are a staple and a great beginner crop for gardeners, farmers, or homesteaders. They can even be grown in pots for those with limited space.
With so many suggestions and little information on growing potatoes no wonder everyone is confused. I compiled this article as a concentrated amount of information. Please let us know if you have any tips, successes or information to add.
What Type to Grow
When deciding what potato to grow it is not so much your growing zone; but what you like to eat. A common way to prepare these starchy tubers is to make them into french fries. Not every potato is suited to become a french fry. ChefSteps suggests, Russet Burbank or Maris Piper, that are not too dry or too wet.(1) According to Huffington Post, there are 10 mistakes that keep me from making the perfect mashed potatoes. While I assure I use enough butter; I do like Purple Majesties as mashed potatoes. Huffington Post, suggests much more starchy potatoes such as Russets, Gold Rush and Yukons.(2) Michigan University’s Potato Breeding and Genetics Program, states that red skin potatoes are great for boiling. Fingerlings are good eats when baked.(3)
This is a second factor in what you can or will want to grow too. Potatoes can be broken into 3 groups. Early-Season Potatoes are ready to harvest in approximately 65 days. Mid-Seasons can be harvested within 80 days. Late-Seasons take more than 90 days to harvest.(4)
Before We Get Technical
This article is very specific. Potatoes are a low maintenance crop. They are considered on of the easiest crops to grow; great for beginners. In poor soil with little maintenance, I have seen people have a 1 to 7 yield; 1 to 10 is the average. I have included a video, “Growing Potatoes the Lazy Way. Simply by increasing the mulch so that the light did not reach the tubers; would have increased their usable yield. So please do not panic or be dismayed. This article is a concentration of usable information; -not musts. There are only two musts in the entire article, the rest is guidelines.
Requirements & Maintenance
Soil will ideally be sandy, with organic material and loamy. Well-draining soil is essential to avoid rot. Sawdust is even used by some growers, with a powdered fertilizer mixed in. PH is debatable. Cornell University, suggests 4.8-5.5 PH. Michigan State University suggests 5.5-6.0 PH. I start my potatoes at 4.5 as the water I use has a PH level of 7.0. Scabbing on tubers will occur at 6.0 PH. (Eating scabbed tubers is not harmful, just ugly and yields a smaller potato.) N-P-K should be 12-12-12.
Potatoes require 6 hours of sun. Water potato bed with 1” of water a week, by rain or design. Two inches of water a week is advisable in soil that dries quickly. Overwatering can lead to scabbing or rot. Under watering can lead to stunting or a dramatic death. Mulch soil with 2” of mulch to keep soil wetter longer. Aged wood chips, or sawdust, sap the soil of the least amount of nitrogen. Clean hay and raised beds are advisable for wetter zones and soil that drains poorly.
Cut larger tubers into sections larger than 1” with 1-2 eyes. Keep the sections in a humid, 60 to 70 F location; 1-2 days. The pieces will have a tougher outer layer that will protect them from rotting in the ground. The potatoes will sprout at 40 F. This means your crop can be started 2-4 weeks before the last frost. Spacing should be determined by variety. However, 3-4” deep, 1’ apart, in rows 2’ apart can be used as a guideline.
Obviously, just starting with the right PH to avoid the plant wasting energy on trying to heal scabs. Second, obvious is to not allow weeds. Third obvious is grow -at the -right time. Potatoes do not grow well in temperatures above 70 F. If tuber plants are not well established by the time heat gets to them they will rot or be stunted.
Potatoes grow best with soil containing sulfur. The reservoir we live by is called Sulfur Lake. Hence, we do not need additive. However, sulfur is fairly cheap and it increases yields. If purchased from a garden distributor, follow instructions on the package as concentrations are different. Remove flowers to increase potato yields. Cutting a few potato greens off a plant will allow energy to be diverted to growing tubers. A note of caution; do not remove too much foliage at once. Pruning too much foliage can send a plant into shock. Crop rotate. Do not grow potatoes the next year, in the same soil as peppers and tomatoes; as they are susceptible to the same pests.
To Hill or not to Hill
Hilling does increase yield. Hill once every couple week once plants reach 6-8” tall. To hill, cover all but 4” of potatoes’ greens with mulch or soil as potatoes grow. This can be done up to 8”. Hilling does take effort and resources.
For those who do not wish to expend either, plant a seed potato 7-8” deep. This is the way I plant my mother’s potatoes. This allows me to put down landscaping material with 4” holes where chits are planted; to avoid long hours of weeding and pests. Because of Wyoming wind, even if the mulch and soil are weedless, there will be weeds. The landscaping fabric with deep growing potatoes produces a higher yield -for my mom, due to the unwillingness to weed -until the plants are nearly overwhelmed. She grows weeds really, really well.
The container is almost as important as the soil. DO NOT GROW IN TIRES. Tires off gas. I know they are super cute all painted up, but stop and don’t. Containers should have ventilation Wood can be used, untreated or treated with real boiled linseed oil. For high wind areas, wood is ideal. Large fabric growbags are ideal for non-windy areas. I have used cardboard boxes in a pinch. Some life hackers use reusable grocery bags. The options are many.
There are a few options to jump starting a crop. The first is to jump start the plants early indoors. Place the cut sections of chits in a breathable bag. Leave at room temperature until the potatoes sprout. This may take up to 4 weeks or as little as 1 day. You can also plant 4-6” deep. Place loose, lightweight-mulch on top of soil. Use enough mulch to prevent light reaching tubers, even if 1 foot is required.
DO NOT EAT GREEN POTATOES. Green potatoes have a higher concentration of solanine, due to light exposure. Symptoms are similar to food poisoning: vomiting, diarrhea, and abdominal pain.(5) Do not eat potato sprouts either. While the sprouts do contain solanine as well; it is unlikely enough to make you sick. However, solanine is bitter and not a great additive to mashed, boiled or fried dishes.
Harvest depends on potato variety. Most potato varieties, the green foliage starts to wilt when it is time to harvest. When you notice the leaves starting to die, you can cut the foliage stalks 1” above the ground. Leave them for 1-2 days without watering. This will potato skins to toughen. Dig up tubers with a fork or garden spade. Remove most dirt, but do not wash.
An early harvests can be used right away or within a few weeks of harvest. However, if you are storing a crop, potatoes must have a tougher skin. Not all varieties are good choices for storing.
Cure & Store
Potatoes should be kept in the dark to avoid turning green. Keep crop at 55-60 F for 2-3 weeks to allow bruises and scabs to heal. For long term storage, keep -healthy potatoes in a well-ventilated container or bag. Long term storage temperatures are above freezing, ideally, 40 F. Remove tubers that are starting to soften first; as they can ruin the bunch.
(1)ChefSteps. “Finding Perfect French Fry Potatoes.” ChefSteps. 2013
Article on potatoes and oils; suited for fries.
(2) Aiken, Kristen. “The 10 Mistakes Keeping You From Making The Most Perfect Mashed Potatoes Ever.” The Huffington Post. 02 Dec. 2013.
(3) Zarka, Kelly A., Donna C. Kells, David S. Douche, and Robin C. Buell. “MSU Potato Breeding and Genetics.” Michigan State University, 2015.
A full article on growing and caring for potatoes. The section on how to cook common varieties of potatoes. A chart about pest and disease control.
(4) Cornell University. “Home Gardening – Vegetable Growing Guides.” Explore Cornell, 2006.
State potatoes growing requirements and available potato varieties to grow.
(5) Lerner, Rosie. “Potatoes Turning Green.” Indiana Yard and Garden Purdue. Purdue University, 18 Oct. 2016. Web. 23 Oct. 2016.Focus, Potatoes