Solanum tuberosum

Solanum Tuberosum

( so - LAY - num too - bur - OH - sum )

"What I say is that, if a man really likes potatoes, he must be
a pretty decent sort of fellow."
- A. A. Milne

introduction

These starchy root vegetables are staple foods in cuisines across the world, and are primarily native to southern Peru and extreme northwestern Bolivia. These perennial plants produce edible underground tuberous roots and above-ground foliage that typically reaches about 3 feet tall. Potatoes are a classic home vegetable garden crop and are simple and fun plants to grow for all ages. Potato plants are members of the species Solanum tuberosum, making them close relatives of Eggplants (Solanum melongena) and Tomatoes (Solanum lycopersicum) Take care when planting these crops in the garden, as any green plant parts including tubers, sprouts, leaves, and fruits, are toxic to humans and pets if ingested.

Solanum Tuberosum Varieties and cUltivars

Solanum tuberosum is just one of around 1,500 species in its genus, which is a member of the Nightshade plant family (Solanaceae). The following varieties and cultivars are just a sampling of the vast array of potatoes available to home and commercial growers for cultivation.

Adirondack Blue
With blue flesh and skin with a slight purple tint. 70-90 DTM.

Adirondack Red
This variety has red flesh and skin. Early to mid-season, high yield. 80-90 DTM.

Agata
Dutch early maturing potato variety with yellow skin and flesh. 70-90 DTM.

Almond (Mandel Potato, Swedish Peanut Fingerling)
Yellow to white with an oval shape. Old variety popular in Europe. 90-120 DTM.

Alturas
Russet potato variety that does well in the Pacific Northwest. Made for processing. 120 DTM.

Amandine
Early potato variety first bred in Brittany, France. Long tubers with pale skin. Matures early.

Amflora (EH92-527-1)
This GMO cultivar that is grown commercially for its starch content. 110-150 DTM.

Anya
A fingerling potato variety with pink-beige skin and white flesh. Nutty flavor. 98-112 DTM.

Atlantic
This variety produces brown tubers with white flesh and is commonly used for chipping. 85-110 DTM.

Austrian Crescent (Kipfel)
Medium-maturing yellow potato good for salads and roasting. 90-115 DTM.

Bamberg
These are long, irregularly shaped potatoes with a waxy texture. Yield is rather low. 110-135 DTM.

Belle de Fontenay
Small fingerling variety with yellow skin and flesh. French heirloom circa 1885. 70 DTM.

Black Champion
Purple-skinned round, flattened tubers. Old garden variety. 100-130 DTM.

British Queen
White kidney-shaped mid-season potato with great flavor. 84-112 DTM.

Butte
Late-season classic Idaho baking potato with good protein content. 110-135 DTM.

Chiloe
A variety of potatoes from the Chiloe Archipelago in Peru and Bolivia. 150 DTM.

Desiree
Red-skinned potato with distinctive flavor. Drought-resistant. Good for roasting, mashing, and salads. 85-120 DTM.

Gala
Early-ripening potato with firm medium yellow flesh, and bright yellow skin. 70-80 DTM.

Golden Wonder
Late russet ideal for baking, roasting, and frying. Will disintegrate if boiled for too long. 140-154 DTM.

Home Guard
Irish variety with moderate to low yields of white creamy potatoes that tend to discolor when cooked. 70-84 DTM.

Irish Lumper
White potato famous for being implicated in the Great Irish Famine. 90-120 DTM.

Jersey Royal
Commercially grown variety with very thin skin. 84-91 DTM.

Kennebec
White potato grown commercially for chip production and fresh market. 70-90 DTM.

Kerr's Pink
Scottish potato variety with pink skin and deep eyes. Good for mashing, chipping and boiling. 125-140 DTM.

King Edward
White skinned with pink areas and shallow eyes. Very old variety used for roasting, mashing, and chipping. Makes good gnocchi. 110-150 DTM.

Laura
Mid-season potato with red skin and yellow flesh. Rich flavor and firm flesh. 90-110 DTM.

Marcy
Late-maturing white potato used for chipping, baking, and boiling. 85 to 95 DTM.

Marfona
Waxy textured potato with light brown to yellow skin and yellow to cream-colored flesh. 84-119 DTM.

Maris Piper
The most widely grown potato in the U.K.; used for roasting, mashing, and chipping. 125-140 DTM.

Megachip
Round white potato that produces high-quality chips with excellent color and flavor. 90-100 DTM.

Melody
Yellow potato with smooth skin and dry flesh, good boiled or mashed. 100-110 DTM.

Ozette
Oldest variety of potato grown in the Pacific Northwest. Petite fingerling potato with tan speckled skin and deep eyes. 100-130 DTM.

Pink Fir Apple
Long, knobbly potatoes with pinkish skin and creamy waxy flesh. 110-130 DTM.

Ranger Russet
Late-maturing russet potato on moderate to high-producing plants. 110-135 DTM.

Ratte (La Ratte)
Nutty-flavored spud with buttery texture with golden speckled skin. For mashing, salads, or casseroles. 90-200 DTM.

Red Gold
Red-skinned potato with yellow flesh. Mid-season. 70 DTM.

Red Norland (Baby Reds)
Often boiled or used in potato salads, this variety produces small red potatoes with waxy white flesh. 70-90 DTM.

Red Pontiac (Dakota Chief)
Red-skinned potato with white waxy flesh. Early-maturing variety. 80-100 DTM.

Rooster
Dull red tubers with yellow floury flesh. Easy to peel, and used for boiling, mashing, chipping, roasting, and steaming. 105-140 DTM.

Russet Burbank
Good for mashing, baking, and chipping, these are commonly cultivated potatoes. 85-120 DTM.

Russian Blue
Medium-sized round and oblong tubers with deep purple flesh and greyish skin. Similar in texture to russets. 60-90 DTM.

Shetland Black
Dark purple heritage-type white-fleshed potato good for roasting, steaming, baking, or chipping. 110-120 DTM.

Superior
White-skinned white-fleshed potato harvested mid-season. Good for chipping. 65-90 DTM.

Umatilla Russet
Great for frozen French fries, with tan skin and creamy, light-colored flesh. 150 DTM.

Vitelotte
French blue-violet potato cultivar with almost black skin. Nutty flavor, chestnut smell. Matures late and is low-yielding. 70-90 DTM.

Vivaldi
Potatoes with yellow skin and pale yellow flesh. Smooth texture. 80-90 DTM.

Yellow Finn
Medium-sized tubers with yellow flesh and white to yellow skin. 115-120 DTM.

Yukon Gold
Popular Canadian cultivar which produces tubers with thin smooth skin and yellow flesh. 60-90 DTM.

Caring for Solanum Tuberosum

Choose a spot in the garden that receives full sun for planting Potatoes; ideally, they like to get between 6 and 8 hours of sun each day to produce well. Potatoes are typically purchased as seed tubers from a reputable nursery or seed distributor. The ideal seed tubers are small and whole, about one to 1.25 inches in diameter. Tubers this size will not need to be divided. Larger tubers should be cut into 1.25 inch chunks. Every piece must have one eye to be viable; two or three eyes per piece is ideal. Leave newly cut divisions out at room temperature for a few days until the cut side has dried out and formed a protective layer. Ensure that soil is well-draining, light, and free from hardpan layers or large rocks. Potatoes grow best in soil that has a slightly acidic pH (between 4.8 and 5.8). If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Set out seed tubers as soon as the soil warms, cut side down 3-5 inches deep and spaced 10 to 12 inches apart. Rows should be spaced 30 to 36 inches apart. Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. A layer of mulch can also ensure that tubers are in enough darkness that they do not develop green areas, which make them poisonous.

Water newly planted tubers regularly, soaking the soil all the way twice a week. At maturity, deep water once a week. During each irrigation, ensure that water is reaching all the way down to the base of the hill. Once green shoots emerge from the soil and reach a foot tall, begin to build up the hill, adding more soil as foliage grows (typically once or twice more during the growing season). At the end of the season, the hill should be between 6 and 8 inches above the soil surface. Prune to remove dead, damaged, or diseased foliage and any flower spikes that form towards the end of the growing season.

Harvesting and Storing Potatoes
On average, a potato plant will produce 6-10 lbs of potatoes (about 50 lbs of potatoes are produced by 2lbs of seed potatoes). It is recommended to plant about 15 to 20 potato plants per household member per year. Potatoes take between 60 and 120 days from sowing to maturity; early varieties are ready as early as 55-70 days, mid-season types take around 70-100 days, and later season varieties can take from 90-120 days to mature to a harvestable size. They are harvested between the months of June and October, a key sign of tuber maturity being yellowing and dieback of foliage and the appearance of flowers. Carefully dig around the exterior of the plant, using a trowel or garden fork to gently lift. Once plants are loosened, they may be able to be pulled up by their foliage. Handle potatoes gently to avoid bruising, and remove a majority of the dirt and debris. Lay them out in a cool, dark, well-ventilated area for between 1 and 2 weeks' time. This will allow skins to toughen in preparation for storage. Keep potatoes stored in a cool, dark, dry place away from direct sunlight and onions. Do not store potatoes in the refrigerator, as the cold temperature converts the starches into sugar. Check stored potatoes regularly for soft spots or rot and remove them promptly to prevent contamination. Potatoes that are stored properly can last for several weeks to several months.

Propagation

Division of existing tubers is the best way to propagate Potato (Solanum tuberosum) plants. They can be propagated via seed, as well, though resulting plants will not be identical to parent varieties. Take care when working with Potato plants to not leave any green parts, including berries, out where children or pets could ingest them, as they are toxic. To propagate your Potato plants, follow the directions below:

Propagating Solanum tuberosum by Division
This type of propagation is relatively simple; you will need a clean shovel or garden fork, mulch, fresh soil, and compost. Division is best done in spring on tubers that were dug up the previous fall. To propagate by division, follow these steps:

In fall at harvesting time, gather your materials. Using a shovel or garden fork, dig up your existing plant. Start from the outside and work your way in to avoid damaging the tuber roots. Once you have worked it up out of the ground, lay it out.
Remove any dirt or debris from the tubers, and bring them indoors to a cool, dark, dry place. Leave them be for two weeks while their skin thickens. After this period has passed, store them in a similarly cool, dark area with good ventilation. These tubers should stay viable through the winter months until springtime.
In spring, choose tubers that are between 1 and 1.25 inches in diameter. If there are no small tubers, cut larger tubers into 1.25 inch diameter pieces, each with at least one (ideally two or three) eye(s). Leave newly cut divisions out at room temperature for a few days until the cut side has dried out and formed a protective layer.
Prepare your pot(s) or new planting site(s) with amended, well-draining soil. You can either bring in new soil or simply amend your existing soil with compost to complete this task. Then, plant your divisions with the eyes facing upwards 3 inches deep and 10-12 inches apart. Rows should be between 30 and 36 inches apart. Water thoroughly.
Follow the care instructions in the section above.

Propagating Solanum tuberosum by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. If you don't have any potting medium on hand, you can make some. Just mix together equal parts (by volume) moss peat and horticultural-grade sand or grit sand. You will also, after a few weeks, need individual 3-inch pots for each seedling that grows.
Harvest your seeds. They are contained inside of berries produced by plants in fall, and are ready to be harvested when they start to drop from their attachments naturally. Bring the berries inside and cut them to remove the seeds, which are typically tan to whitish and small. Like Tomato seeds, Potato seeds need to be fermented. Place seeds in a container and add hot water. Shake or stir several times a day. Allow the seeds to ferment in the water until a white scum is formed on the surface and most of the seeds have sunk to the bottom. The scum and any seeds that float can be scooped off with a spoon and discarded. Take a seed out as a test to see if it has shed its gel, and if it has, pour the fermentation container through a sieve to remove the seeds, and then rinse them repeatedly until they are all clean. Put the seeds out onto a clean surface and allow them to dry. They can then be stored in a cool, dark, dry place until they are needed.
In springtime, water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 2-4 weeks from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
Seedlings can be planted out in the early springtime when soil temperatures have risen to at least 45 degrees Fahrenheit.