Whether you like them baked, mashed, or cut into fries, potatoes are one of the most versatile vegetables in recipes. Potatoes are easy to grow for most novice gardeners, and various varieties suit climates all around the United States.
Before we start with our guide on planting, growing, and harvesting potatoes, we thought we would give you some time-tested tips;
The Dutch settlers in Pennsylvania regarded March 17, otherwise known as “St. Gertrude’s Day”, or St. Patrick’s Day for the Irish – as the official potato planting day.
It’s a tradition in New England to plant potatoes when dandelions start showing up in fields. Many Irish Christians believe that planting on Good Friday is best, as the devil holds no power over the earthly realm on this day.
One thing that ties all of these legends together is – plant your potatoes in the early springtime.
When to Plant Your Potatoes
Start your potatoes 2-weeks after the last frosts settle on the ground. Check your local listings for frost dates in your area, and then make your planting preparations around the final frost. If you live in warmer regions of the United States, you can start your potato crop 2-weeks before the beginning of spring.
If you live in an area that gets a late spring, then you can still plant potatoes up until mid-April. If you’re planting in barrels or potato towers in a greenhouse, you can start your crops as late as June, and still receive a decent harvest.
How to Plant Your Potatoes
There are plenty of ways to plant your potatoes. One of our favorite methods is using raised beds. Raised beds in a greenhouse is an even better option. Raised beds provide better airflow to the roots, producing bigger harvests.
If you’re growing in pots or containers, then we suggest you look into material pots. These containers have permeable edges made from non-toxic materials. Air flows readily through the materials, letting your potatoes breathe.
If you decide on raised beds, then we recommend you build a bed that’s no less than 36 to 42-inches in height. Old reclaimed wood is a good idea or three or four old tires with the sidewalls cut out will do you fine.
It’s possible to grow potatoes in a potato tower or specialist grow bags as well. These are specialized growing towers designed to hold multiple potato plants at once. Using a tower minimizes the footprint of your garden or greenhouse, getting more production per square foot.
However, if you want to do things the old-fashioned way, then growing in the ground will always give you a good crop. Dig a trench in your garden to make a bed. Move the soil to form a channel that’s 6-inches wide and 8-inches deep, and taper the bottom to around 3-inches in width.
Grow your potatoes in rows, and space them at 3-feet apart. Spread some rotting compost or cured manure into the trench to add nutrients to the ground. In your channel, plant a seed potato piece, with the cut side down, every 10 to 12-inches apart, and then cover it with 3 to 4-inches of compost and soil.
The best potato starters are seeded potatoes with protruding eyes. It’s essential that you don’t confuse seed potatoes with those that you get from your local grocery store.
Caring for Your Potato Crop
It’s essential to keep building soil over your potato plant as it grows. If the tubers have any exposure to the sun, they start to turn a green color. These potatoes taste bitter and become hard.
Potatoes like plenty of water, and they prefer and even and consistent approach to watering. Leaving your potato crop without water for a few days on end every few weeks will result in green and hard potatoes.
We recommend you give your potato plants at least 1 to 2-inches of water throughout the week.
You’ll need to start to increase your watering slightly when the tubers begin to form. When the summer sun gets hot, the potato plant may start to droop. You can support the plant and keep the leaves off of the floor using a trellis.
Hilling also supports your potato plant and prevents your tubers from sustaining a sunburn. Potatoes that turn green produce a toxic substance called solanine that gives the potatoes a bitter taste. If you eat green potatoes, you could end up with an upset tummy.
Pests and Diseases Affecting Your Potato Crop
There are a few pests and diseases that affect your potato crop. Here is what you need to look out for during the growing season.
Potatoes grown in soil with a pH above 5.5, will start to develop a condition known as “potato scab.”
Smart gardeners will dust their potato seeds with sulfur before planting. This strategy ensures that no fungi or bacteria attack the potato seed in its juvenile state. Sulfur eradicates mold and other fungi, protecting the plant’s root system.
After planting and hilling, you can add a layer of pine straw for additional anti-microbial protection. Pine leaves have a natural polyphenol antioxidant that acts as a pest repellant and anti-fungal.
One of the biggest problems with managing potato crops is the Colorado potato beetle. You’ll have to check your crop for these beetles every day and pick them off by hand. Some gardeners can try controlling the spread of potato beetles using
Colorado potato beetles need to be hand-picked, and predatory birds will often eat them with Diatomaceous Earth while they are still in the lymph state. If you decide to go with an organic pesticide, make sure you spray in the early morn8ing or late afternoon to avoid harming beneficial insects visiting the garden, such as pollinators.
Aphids and flea beetles also present something of a problem to gardeners in the warmer states. If you live in an area that gets cold and rainy for extended periods, periodically check your plants for mold or mildew and early or late-stage blight.
Potatoes that receive infection with blight require removal. Throw them out with the trash, and don’t add them to your compost heap. The pathogen survives out of the soil and in the ground for months.
You’ll have to learn the art of crop rotation if you want to grow potatoes. Rotating your potato crop ensures that the ground, and the roots of your potato plants, stay healthy.
When to Harvest Your Potatoes
If you want “new potatoes,” which are smaller, around the size of a golf ball, with thinner skin, then harvest your potato crop 2-weeks after the plants stop flowering. You’ll need to eat the new potatoes within a few days after harvest.
For harvesting mature potatoes, we recommend you wait until 3-weeks after the plant’s foliage dies back. It’s critical that you let the tops of the vines die before harvesting your potato plant. Cut back the browning foliage all the way to the soil, and wait another 2-weeks to allow the skin of the potatoes to thicken.
Don’t wait longer than 3-weeks to harvest, or your potatoes might start rotting in the ground. If you want to store your potatoes for use throughout the winter, harden them by minimizing watering after mid-August.
Tips for Harvesting Your Potatoes
Dig up your potato plants on a hot, dry day. Make sure you dig around the base of the plant in a 2-foot diameter to avoid damaging the tubers. Scarred potatoes will rot during storage, and you’ll need to use them within a few days.
During the season, the growth of the tubers, along with your hilling, should make it easy to gig them out of the ground. If you have to dig your potatoes up on a damp or wet day, then make sure you dry them as much as possible before storage. Storing soggy potatoes will end up causing your entire crop to rot in your root cellar.
Don’t leave the potatoes in the sun after digging them up, as they’ll turn green and hard in a few hours. Green potatoes taste bitter and hard, and you might get a case of vomiting or diarrhea, as well.
Trim off the small spots, but throw out the potato if there is excessive greening. Allow your potatoes to sit in a root cellar in dry and cool conditions for up to 2-weeks after harvest. This strategy gives the potatoes time to cure and improves the flavor of the tubers.
After you finish with the curing cycle, brush off any excess dirt using a light brush, and then store your potatoes in a root cellar for up to a month. The root cellar should have an average temperature between 40 and 50F. Make sure the root cellar has plenty of ventilation and good airflow throughout the storage space to prevent rot.
As a tip, never store potatoes with apples. The apples release a gas that causes your potatoes to rot. Avoid storing your potatoes in the fridge, as they’ll turn soft. Only wash your potatoes right before you eat them for the best results in your recipes.