How to Grow Potatoes in Containers
Learn how to grow potatoes in containers; no tilling required. Although potatoes grow best in places with cool summer days and nights (think Idaho), if you choose the correct variety and plant them at the correct time, it’s possible and relatively simple to grow potatoes in warmer climates like Arizona.
Whether you like them baked, mashed, french fried, roasted or any number of other ways, potatoes are a delicious staple. Try a homegrown potato and you can taste the difference in crispness and freshness. If you want to learn how to grow potatoes in containers, you’ve come to the right place.
1. Before you learn how to grow potatoes in containers, understand how potatoes grow
Look closely at a potato; there are several slightly-recessed ‘eyes’ on the surface. Under the right conditions, these eyes sprout – you’ve surely seen this happen to a potato in your kitchen.
When the sprout is planted, it develops into a stem. The stem grows into a plant above ground, and the excess energy from the plant is channeled downward to the roots and stored in ‘tubers’. A tuber is the thickened part of the stem growing underground. We call those thickened tubers ‘potatoes’.
2. Choose the right potato to plant
In climates that have a shorter season, such as the low desert of Arizona, plant “early” and “mid-season” determinate varieties of potatoes. Determinate varieties are faster growing potatoes that produce one smaller harvest quicker (60-90 days) than indeterminate varieties. Varieties to try are Yukon Gold, Purple Viking, and All Red.
If you have a longer growing season choose indeterminate (“late season”) varieties of potatoes. Indeterminate potatoes grow a larger crop with multiple layers along the stem and take between 110 and 135 days to produce. Late season potatoes continue to set new potatoes along the stem until they are harvested or frost kills them off. Indeterminate varieties to try are Russian blue, Canela Russet, and Ramona.
Buy certified disease-free seed potatoes from online retailers or garden centers for best results.
3. Prepare the potato before planting
Put seed potatoes where the temperature is between 60-70℉ and where they will be exposed to light. This encourages the potatoes to sprout (a process called ‘chitting’). Once potatoes have sprouted, if potatoes are larger than an egg, cut it into pieces. Ensure each cut piece has 2-3 eyes.
4. Plant potatoes at the correct time
In cooler parts of the country, plant potatoes just after the last frost date. In the low desert of Arizona, plant from September through January.
Potatoes are frost-sensitive, and the plants will die in a hard frost. If plants are killed by frost, harvest potatoes, no matter the size, within a week or two to keep them from rotting.
5. How to grow potatoes in containers? Pick a container, any container
Potatoes aren’t picky about which container they are grown in. Choose trash cans, compost sacks, or burlap bags. I like growing potatoes in these 40 gallon grow-bags. Follow the basic principles for planting outlined below, and you can be successful no matter which container you choose.
6. Plant the right number of potatoes for your sized container
The most important rule when using containers is to match the number of seed potatoes to the size of container you are growing them in. As a rough guide, each potato plant needs about 3 gallons to grow well. Overcrowding potatoes results in smaller potatoes.
7. Plant potatoes correctly
Place a 3-4 inch layer of loose soil, amended with compost, in the bottom of the container. (Roll down sides of container if desired). Potatoes prefer slightly acidic soil. Use a soil blend made for acid-loving plants or amend soil with an acid mix fertilizer according to package directions.
Plant seed potatoes with sprouted-side up in soil, and cover them with 2-3 inches of additional soil.
As potatoes sprout, cover the sprouts halfway when they are about 6 inches tall. Continue this process until the top of the container is reached at which point the plant will continue to grow without being covered up.
Hilling the potatoes ensures that determinate potatoes are not exposed to sunlight and turn green and ensures a larger harvest of indeterminate varieties.
8. Don’t let potatoes dry out
Potatoes need consistent moisture to grow well. Potatoes grown in the ground look for moisture in surrounding soil while container-grown potatoes rely on the moisture you provide.
For even watering, I have a drip line inserted in each grow bag. It’s important to keep soil evenly damp, but not wet. Allow some drying between waterings.
Consider feeding actively-growing potatoes with an acid -loving organic fertilizer or seaweed extract, each time you add more soil (or once or twice during the growing season). Mulching with straw helps to retain moisture.
9. Put your container in the best location
Potatoes need at least 6 hours of sun to grow well. In the low desert, full sun is preferred for the fall planting of potatoes. Spring-planted potatoes do best with a little afternoon shade to prevent them from drying out too quickly.
10. Know when to harvest potatoes
‘New potatoes‘ are simply immature potatoes that are harvested before the potatoes are fully mature.
For determinate potatoes check 60-90 days after planting and for indeterminate varieties check 100-120 days after planting. Dig down with your hand near a stem to check the size of the potatoes. Harvest potatoes that are large enough to eat as desired.
Harvest ‘new’ potatoes just after the plants flower (if the variety you are growing is one that flowers). For larger potatoes, wait until the tops begin to turn yellow and die back.
To increase the storage time of potatoes, allow them to stay in the ground for an additional 2 weeks following the dieback of the plants.
When you are ready to harvest the entire container, gently dump it out into a wheelbarrow, being careful not to damage the potatoes. Let potatoes cure for a few hours outside. Brush loose soil off the potatoes, and store them in a cool, dry place until you are ready to use them.
New potatoes are best eaten within a few weeks of harvest. Mature potatoes free of blemishes will store longer.