Growing your own potatoes will pay big dividends in flavor and nutrition, especially if you grow them organically. Sure, you can buy a ten-pound bag of potatoes in the supermarket for a song, but have you ever put your nose to the mesh opening on that bag and sniffed? Chemicals, fungicide, heaven knows what! How much butter and salt do you have to put on them to make them taste like something edible?
Potatoes are remarkably easy to grow and so much fun to harvest – almost like an Easter egg hunt! Start with certified seed potatoes available at your local store or through mail order. Grocery store potatoes may look fine but can be harboring diseases. “Chitting” or sprouting the seed potatoes indoors will give you a jump on the season and allow time for more than one crop in warmer zones. A week or two ahead of planting time, spread the seed potatoes out in a single layer on a shallow tray. Place the tray in a warm place with plenty of light. Soon you’ll see white sprouts popping out of the potatoes.
I like to plant whole tubers, but if you decide to stretch your seed potato supply by cutting them up, do it two days before planting. Make sure each piece has two or more eyes. Let them dry in an airy place so the cut will heal. That way pathogens will have a harder time getting in.
Where to Plant
If you have an established garden, choose an area where potatoes, tomatoes or peppers have not grown for at least two years. This will greatly lessen the chance of disease. Potatoes like a warm, deep growing medium so containers, barrels and even grow-bags can be used if you don’t have garden space.
You can plant potatoes early in the spring, but make sure the soil temperature is at least 45 degrees and not excessively wet or the tubers will rot. If frost is still expected, cover the emerging leaves with a light floating row cover which will keep them warm while allowing sunlight and water to penetrate.
The soil pH should be slightly on the acidic side – 6.o to 6.5 is good. Do not use lime on your potato bed or several diseases may become a problem. Another n0-no is fresh manure or hot compost. These can cause scab on the surface of the potatoes. It’s not a serious problem, but it is unsightly and should be removed before cooking.
An easy way to plant potatoes is to dig holes one shovel-depth (6-8″) deep and 12-18″ apart. Place the soil to one side of the hole for future filling up. More on that later. I always put a couple of handfuls of finished (cool) compost in the bottom of each hole. Two other very beneficial soil amendments which can be added at this point are greensand (provides extra potassium) and kelp meal. I once ended up with a big box of dried kombu (Pacific kelp) that a vegetarian friend decided he would never eat. I broke a few 4″ pieces of the seaweed into each planting hole in the spring. Come harvest time I had my best potato crop ever!
Place one tuber or piece in each hole and cover with a couple inches of soil. If your potatoes have sprouts, be very careful not to break them off. If a few do break, don’t worry. Look closely at the seed potato and you’ll see that there are a couple more back-up eyes from which new sprouts will come. In a week or two green leaves will start to poke through the soil. As they grow add more soil to the planting hole until you’ve used up the soil from digging the original hole. This is known as “hilling up”. It’s important to make sure the growing potatoes are covered to avoid green patches from sun exposure. The green patches can be toxic so be sure to cut them off before cooking. Several inches of mulch will prevent greening as well as conserve moisture and keep weeds from growing. Apply the mulch after the final hilling.
During the Growing Season
If large potatoes are your goal, early on remove all but two or three stems from each hill by giving a short, sharp tug to the weaker stems. They will pop right off the tuber. Throw them in your compost pile.
Be sure to provide adequate moisture in the first two-thirds of the growing season. I run a drip irrigation line down each row, placed about six inches away from the plants. This way the potatoes get enough water without drowning. Drier soil is an advantage during the last third of the growing season as it promotes healthier tuber formation. Rain can’t be controlled, but avoid heavy watering at this time.
I find that spraying fish and seaweed emulsion on the potato foliage at two week intervals makes the plants strong and keeps growth vigorous. Follow the dilution rates on the container. Don’t use heavy nitrogen fertilizers or you’ll end up with a lot of green leaves and very small potatoes.
When flowers appear you can feel around very gently under the plants for new potatoes. “New” simply means small, young spuds which are delicious steamed or fried quickly in a little butter or olive oil. I take only one from each plant so my final harvest will not be diminished. You can do this about once a week and still get plenty of potatoes. It’s also a good idea to remove flower blossoms as they appear so the plant’s energy is not diverted to seed production.
As the season goes on, the tops of your plants will start to turn yellow and wilt. This means it’s almost harvest time. Let the potatoes stay in the ground to cure for about ten days after the tops die back. Do not do this if the weather is very rainy or if you have underground critters like voles which will dine on your crop.
I love to dig up the potato crop! Choose a dry day and have enough non-plastic receptacles ready so you don’t have to pile the tubers more than three deep. Non-waxed cardboard boxes are ideal. Heavy or doubled paper bags will work too. You want something which will let air through but not light. Potatoes exposed to light will turn green and be inedible.
If your potato crop is growing in a container, just pull off the dead plants and feel around for the tubers, removing soil as you go. In the garden you may need to use a tool. I use a shorter shovel with a handle. Insert the shovel into the soil far enough away from the plant so you don’t cut into any potatoes. Gently lever the blade up to loosen the soil. Remove the shovel. Use your hands to pull back soil and feel around for potatoes. Eureka! What a thrill it is to unearth the big, beautiful spuds! Be sure to probe deep enough and far enough to either side so you don’t miss any. Rub off excess soil but do not wash the potatoes.
Keep the boxes or bags of potatoes in a dry, room temperature place with plenty of ventilation for 1-2 weeks. This will cure the tubers which means their skin will toughen up so they will store longer. Do not try to store less than perfect potatoes – eat them! Keep your crop in a cool, dark, well-ventilated place. The optimum storage temperature is 40 degrees, but I keep my spuds in paper bags under my staircase in a cubbyhole which is against an outside wall. The temperature is probably 50 degrees or so in there, but the potatoes still manage to last from September until March.
My favorite variety and a very popular one in the marketplace is ‘Yukon Gold’. It’s great for boiling or baking and makes delicious golden mashed potatoes that look already bathed in butter. ‘Yukon Gold’ is an early to mid-season variety that stores very well.
Fingerling potatoes are prized because of their wonderful flavor and ‘waxy’ texture which means they don’t fall apart when boiled and are excellent fried. ‘Russian Banana’ is a fingerling potato type. Russets are another kind of potato you will probably want to grow if you like baked potatoes. Their drier flesh make them perfect for that use. Many mail order catalogs are selling interesting potato varieties now so check around for the ones which best fit your needs and gardening zone.