How Do You Like Your Potato?
Potatoes can be grown in your vegetable garden, but also in large containers, garbage cans, reusable potato grow bags or in stacked tires.
I realize that writing a “growing potatoes” blog in Saskatchewan is somewhat akin to telling Newfoundlanders how to fish but there may be a few new vegetable gardeners out there that can benefit from a starter’s guide to this fun and worthwhile process!
Potatoes can be grown in your vegetable garden, but also in large containers, garbage cans, reusable potato grow bags or in stacked tires. Some of these methods allow even condo and apartment owners to grow a few fresh potatoes for a treat! If you do use containers, remember to use large containers with good drainage. Poor drainage in the garden or in a container may encourage seed rot and disease. If you are in a condo or apartment, share a box of seed with friends, family, or neighbors.
Before you purchase seed potatoes do a bit of research. Potatoes fall into three categories. Best for boiling, baking, and best for fries and chips. Note the days to maturity on the box when purchasing as some varieties mature early; some late.
Boiling potato varieties include Norland, Viking, Caribe, Pontiac and Bintje*
Baking potatoes - Russet Burbank, Goldrush and Yukon Gold.*
Potatoes that are used primarily for fries and chips are Atlantic, Yukon Gold and Cal White*
Potatoes like to grow in full sun. Plant only certified, disease-free and resistant potato seed and purchase it early in the spring season.
It has been my experience that potato seed tubers have usually sprouted at time of purchase. If not, you can get a jump on sprouting by practicing the tried- and- true method of chitting or sprouting the potato seed. About 4 weeks before planting – early April in Saskatchewan - put your seed in the dark at 20 degrees C until you see sprouts emerge. You can then move them to a spot where they get ten hours plus of bright light per day. After about two weeks, you will notice the seed potatoes have formed short, stubby green sprouts that will stay intact during planting. When you plant this seed out in early May, you will have potato seed that is well on its way to early emergence.
Potatoes prefer a well drained, sandy loam soil that is amended with well- rotted compost, manure and dampened peat moss. The peat moss is to lower the soil Ph as potatoes like a slightly acidic soil; somewhere between 5 and 7. Manure must be well rotted as fresh manure contains a lot of nitrogen which can burn the plant’s tissue. It can also contain E.coli bacteria which can be deadly. Till the soil well and then wait until the soil temperature is 8 to 10 degrees C or above to plant. Planting in cold soils often results in disease problems.
Small tubers can be planted whole but larger ones can be cut into sections. Each section must contain an eye sprout or two. Let them sit out for two to three days to heal over the cut areas.
Prepare your potato garden soil by tilling and mixing the soil amendments well into the existing soil. Dig narrow trenches 3 feet apart and 6-10 inches deep. Place your potato seed in the bottom of the trench twelve inches apart with the green sprouts facing up. Cover the seed with about 2-3 inches of soil. Do not water between planting and sprout emergence as this may encourage disease. Sprouts will begin to emerge anytime between 14-28 days.
Once emergence has occurred you can begin to regularly water. Potatoes need about an inch of water per week but this varies with weather changes. To avoid splashing the leaves water on either side of the planting trench instead. Do not let the soil become too dry and water regularly when the plants are flowering which signals tuber formation. Uneven watering practices will often result in hollowheart, knobbiness and splitting. When the plant has grown a foot, hill up the soil around the plant stem about another six inches. Do not worry about covering some of the leaves. Repeat this about two to three times as the potato plant grows. As each hilling grows higher, tubers will be formed inside the hill. If you see any newly formed tubers peaking out of the soil, pull soil over these tubers again. Exposed tubers result in sunscald and greening of the skin.
Exposure to too much light can produce greening of the skin which is a chemical called solanine. Solanine is mildly poisonous, sometimes causing stomach upset and headaches. This is easily rectified by keeping stored potatoes in total darkness. When cooking, you can cut off the green skin, taking some of the green flesh underneath as well.
Planting potatoes in grow bags or large containers is a fun way to begin growing potatoes. It greatly reduces disease and insect problems and frees up garden space for other edible plants. Start with a few inches of soil in the base of the container. Place about three tubers on the soil and then cover with about six inches of additional soil. Do not water between planting and sprout emergence. Once the sprouts have emerged, water regularly but do not drown the plants. As the plant grows upward and reaches one -foot increments, add more soil. Again, do not worry about covering some leaves. When the potato plant comes over the rim of your container, add soil again for the last time. Let the plant grow on to produce flowers. Flowering indicates tubers are forming!
New potatoes can be harvested about 8 weeks after planting. If the potatoes are in a container, you can dig down with your hands from the top and pull out some small ones without disturbing a lot of the remaining tubers. Some growbags have easy access from the side for harvesting.
When you would like to harvest your potatoes for winter storage, remove the tops of the plants one to two weeks before digging. The plants may already be deteriorating with age. This toughens up the skin which helps combat dehydration and disease during storage.
Allow newly dug potatoes to briefly dry in the sun and clean off the soil – do not wash it off. Ideally store potatoes in the dark at 4-7 degrees C. Humidity should be 90 to 95%. You can also store them in netted bags or burlap sacks that breathe to allow airflow around the potatoes.
Potatoes can be affected by disease and insect damage. Two problems you may encounter are Scab and Colorado potato beetle.
Scab is actually quite common but is only superficial. It is a bacterial infection that results in corky raised ridges on the potato’s skin. It is spread by infected seed potatoes and can blow in with wind and rain as well. Keeping your potato garden soil slightly acidic with the addition of peat moss will help prevent scab. Use only well rotted manure and compost when amending the soil. It can also live in the soil for many years without a potato crop to infect. If possible, rotate potato crops every season. Plant scab resistant varieties such as Russet Burbank, Russet Norkotah, Goldrush, Viking and Norland.
Another common pest of potato plants is the Colorado Potato Beetle. Adults overwinter in the previous year’s potato garden or in nearby grassy areas. Overwintering adults emerge in late May or early June, feed and then mate. During late May to early June is the best time to hand pick these pests as they are fairly large and easy to see. This will help break the insect’s life cycle. If a few get by you, they may lay small yellow masses of eggs on the underside of the leaves. The eggs will hatch into larvae which can be easily picked off as well. Get the kids involved in the picking process- they usually find it fun and it’s a great learning experience!
As mentioned, this has been a beginner’s foray into growing potatoes. I would appreciate hearing back from the more experienced vegetable gardeners with tips and tricks they have found useful when growing potatoes in Saskatchewan!
*Potato cultivars mentioned here may or may not be carried by Floral Acres 2021.