The first thing to consider when you start your potato journey is how you are going to grow your potatoes and how much space you have to devote to the process. Will you use a potato bag with or without flaps? a 5-gallon bucket? a plot of ground? a plastic trash can? Or some other more original method?
Once you have decided, it will help you with your next task of buying the actual seed potatoes.
Purchasing Potato Seed
There are more than 5000 varieties of potatoes. So the next task is figuring out which type you are going to invest in. Oftentimes, I pick varieties that are fun to look at. For example, Masquerade potatoes are variegated purple and white. While they are beautiful, they are also tasty. However, we have always found them to be low yielders compared to some other varieties. Do we still grow them? YES because they are fun to look at and great tasting. Thus, when choosing, read the descriptions. A few general things to consider are taste/texture/uses, maturity date, color, and size or type.
After that, you need to consider how much space you will be allocating to potatoes. If you are planting in the ground, some general estimates for regular potatoes are (at 10-12” between plants):
1 pound plants 5-8 row feet.
2.5 pounds plants 12-20 row feet.
5 pounds plants 25 row feet.
20 pounds plants 100 row feet.
Fingerling potatoes are a little different. They use about half the weight for the same row footage (typically much smaller potatoes with relatively high yields). If using a container, a good estimate to use is 2-4 potatoes per 5 gallon bucket (bear in mind that larger seed potatoes can be cut into segments with 3-4 eyes each and do just as well as a whole seed potato).
When TO PLANT
Garden potatoes can be planted 2 to 4 weeks before the last frost date in the spring. Find your climatic zone to figure out when that is. Generally speaking, this is late spring in our neck of the woods (Late April – May). However, they won’t start growing until the soil has warmed to around 45 degrees. So be more alert to the soil temperature than the calendar to determine planting time.
If you find you have planted too early, one solution is to cover the ground or pots with some sort of protective layer (e.g. floating row cover, clear poly, etc) to keep the soil warmer until the plants emerge.
For example, we are in Zone 5b. Most years many local farms near us start planting in April. Unfortunately, with our spring laden fields, we are unable to get on our fields till May, or we would be planting mid-April as well.
GRowing FROM TUBERS
Potato plants grow from tubers (the spuds themselves) planted about 6” deep in the ground, about six to eight inches apart (10-12” for larger varieties). Potatoes are notoriously hard to get every potato out of the ground. If you don’t want a few stragglers back each year, I would suggest growing in a container of some sort.
Unlike many vegetables, potatoes thrive in acidic soil (pH 6-6.5). They can grow with a soil pH as low as 5 (think rocky crags in the mountains of Peru, where they were originally domesticated for agricultural use. They prefer a well-drained; sandy loam soil, but tolerate a variety of soil types. The leaves and stems of potato plants love full sun. The actual potatoes do not.
You do not need to hill the potato plants. Although, we find it a very effective method for a higher yield of potatoes. Once the plants reach about 8 to 12 inches high, use a hoe to push dirt around the stems, being careful to almost, but not completely, cover all the stem and leaves except for the top couple inches. This prevents tubers from coming to the surface and being exposed to (and ruined by) the sun. If you decide to grow in a pot, bucket or bag, do not fill them all the way. This will leave room for you to add more soil later to replicate a hill in the field. Repeat every couple of weeks as the stems grow until the soil height nears the top of the container.
Keep potato vines well-watered during the summer, especially during the flowering stage. This is when the plants create their tubers, so a steady water supply is crucial for a good crop. Potatoes do well with one or two inches of water per week. Stop watering if the foliage turns yellow and begins to wither. This helps cure the potatoes for harvest so they store better once picked.
Make sure to weed potatoes regularly in the beginning until they can shade out the weeds below (hilling also helps with weed control).
Potatoes are heavy-feeders, which means they need a nutrition boost to grow well. Add a handful or two of good-quality compost (or the recommended amount of your preferred fertilizer) to your potatoes when you plant the tubers, and dress them again midway through the season.
PESTS & DISEASE
The starchy flesh of potatoes attracts pests, including wireworms, a larval form of click beetles that feed on tubers. Moles, voles, and mice also love to gnaw on them. The Colorado potato beetle can wreak havoc on young potato plants, eating them down to almost nothing. We have found the best control is to use an approved organic pesticide (Spinosad). We spray a day or so after we see the first hatch on numerous plants. Companion planting is also supposed to help some. Planting potatoes near coriander, nasturtium, onions or marigolds is said to help deter the Colorado potato beetle. We can’t personally speak to the effectiveness of this avenue. On a smaller scale, hand picking of larval potato beetles is highly effective as well.
Fungal and bacterial rot can damage the roots, especially if the tubers are grown in damp soil. Fusarium wilt stunts the vines and creates hard, dark spots on the potatoes. Prevention is the best defense, so plant your tubers in well-drained soil. Make sure never to replant infected tubers or use them for seed because disease can be passed along to the next generation. The leaves and stems are also susceptible (by varying degrees based on variety) to Early and Late Blight, a fungal pathogen that comes in on the breeze and proliferates in damp conditions. A well-spaced, sunny location with good air movement is helpful at preventing blight losses. Large scale organic producers can use copper based anti-fungal applications to ward off fungal agents as well. We limit the use of this on our farm, however, as repeat applications in the same area over time can be detrimental to soil microbes and insects.