How Often to Water Potato Plants for a Successful Crop Jenny Graham, January 28, 2024January 28, 2024 Are you new to growing potatoes and are wondering how often to water potato plants? Before we dig in and start planting let’s talk how often to water potato plants. How Often to Water Potato Plants? During the growing season, depending on your climate, you may find that you need to water your potato plants every couple of days. If it’s the rainy season, you may not need to water at all. They do like consistent soil moisture so frequent watering is a good idea. How Often to Water Potato Plants During the Growing Season? How often to water potato plants often depends on your climate and how much rain you receive. Having a rain gauge nearby will help you determine how much you need to water your vegetable garden. As a general rule of thumb potatoes need moist soil and about 1-2 inches of water a week. How Often to Water Potato Plants After Planting? You’ll want to be sure to water your potato seeds after planting. For best results, be sure they are planted in well-drained soil. Be cautious though, as too much water right after planting can cause misshapen tubers. How Often to Water Potato Plants for High Yields According to Montana State University, potatoes are quite sensitive to moisture stress over much of the growing season, so they need relatively high soil moisture levels (60-80% of the available water capacity) to achieve high yields and quality. They also need consistent moisture to grow. How Often to Water Potato Plants for End of Season Once your potato flowers bloom, be sure to keep a steady water supply at 1-2 inches per week. Once the foliage begins to turn yellow and die off you can stop watering. How to Water Potato Plants While some people water their potato plants with overhead irrigation, like sprinklers, some home gardeners go with bottom watering or drip irrigation. In my garden, it’s all about bottom watering potatoes. Things to Consider When Watering Potato Plants The reason for the debate on how to water your potato plants is blight and other fungal diseases. Many fungal diseases thrive warm wet conditions. Overhead watering of potato plants creates the perfect environment for fungal disease to take over in hot weather. Mulching Potato Plants to Conserve Water A layer of mulch around your potato plants is a great way to maintain the moisture in the soil. When it comes to bark vs mulch in the vegetable garden, your choices matter so be sure to do your research. Keeping the moisture consistent and soil temperature on the cooler side while growing potatoes will help ensure you have a successful crop of potatoes. Where to Get Seed Potatoes I have found that I prefer to buy my seed potatoes at my local farm and garden store. They only carry a few varieties, which all do well in my area. If I did want to branch out and try a different variety I would order from HossTools. They have multiple, high quality, varieties to choose from. Some gardeners have even had luck with grocery store potatoes. If you go this route, just be sure to buy organic so they haven’t been sprayed with anything that may keep them from sprouting or chitting. Chitting Seed Potatoes Chitting seed potatoes is the process of allowing them to sprout. This can be done before or after cutting your seed potatoes to plant. To encourage chitting you can prop potatoes up in an egg carton in an area that gets good indirect light. Ideally, you’ll want to start encouraging seed tubers about 4-6 weeks before you are ready to plant your potatoes. Cutting Your Seed Pieces Larger seed potatoes need to be cut into smaller pieces to get the most out of your seed potatoes. Ideally, you’ll want 2-3 eyes or seed tubers on each of your seed pieces, cutting them into nice sized chunks. I usually try and cut larger potatoes into four chunks, while smaller potatoes are often cut in half. When to Plant Potatoes Ideally, you’ll want to have your potatoes planted 2-4 weeks before your last chance of frost in the spring. If you are in a warmer climate, you’ll need to have your seed potatoes in the ground sooner than later, as they are a cool weather crop. You may find though, that your young potato plants will appreciate row covers for that last frost. Knowing your growing zone and average last frost date will help. Planting Potatoes by Zone Zone 10 January 15 – 31Zone 9 February 1 – 28Zone 8 February 15 – March 15Zone 7 March 1 – 31Zone 6 March 15 – April 15Zone 5 April 1 – 30Zone 4 April 15 – May 15Zone 3 May – June Where to Plant Potatoes For the best potato crop, plant your potatoes in an area that gets at least six hours of full sun. They will do best in loose, sandy soils with lots of organic matter. Potatoes prefer fertile, well-drained, slightly acidic soil. Soil Preparation for Planting Potatoes Since potatoes are root vegetables, they prefer a soil that is loose and well-draining. I prefer to use a broadfork to loosen to soil as opposed to tilling the soil to prep for potato planting. Additionally, removing all weeds and grass in the vegetable garden is essential so they don’t rob your plants of essential nutrients. How to Plant Potatoes While some home gardeners plant potatoes in containers or grow bags, I prefer to plant them in rows for the sole purpose of growing a bunch. It’s always wise to do a soil test to see exactly what soil amendments yours oil may or may not need. After amending and loosening the soil with a broadfork or pitchfork, dig a trench down your row, about 3-6 inches deep. Depending on the variety, plant your potato seeds 6-12 inches apart, covering them up with a couple inches of soil or compost. Once you see sprouts come through the first couple inches of soil, go ahead and cover them up the rest of the way. From here, you’ll need to know whether you are growing determinate or indeterminate potatoes to know what comes next. Growing Potatoes in Traditional Garden Rows Row Spacing should be 3 to 4 feet Plant Spacing, depending on variety, 6 to 12 inches Planting Depth is 3 to 6 inches Growing Potatoes in Containers Row Spacing at around 2 feet Plant Spacing, depending on variety, 6 to 12 inches Planting Depth is 3 to 6 inches Do All Potatoes Need to Be Hilled? It’s a common misconception that all potatoes need to be hilled, which is why it’s important to know what variety you are growing and if it is a determinate or indeterminate variety. They both have different growing requirements. Determinate Potatoes Determinate potatoes are a quicker growing crop of potatoes, usually maturing in 70-90 days, depending on the variety. They do not need to be hilled as they are growing. Potatoes will grow in one layer a few inches under the soil where the seed potato was planted. Early or Mid Season Determinate Potatoes Colorado Rose Norland Red Yukon Gold Kennebec Viking Huckleberry Gold Pontiac Red Indeterminate Potatoes Indeterminate potatoes need more time to grow, taking 110-135 days to mature and require much hilling. They grow tubers up along the stem, so hilling them as they grow will give you good yields. Late Season Indeterminate Varieties French Fingerlings German Butterball Russet Yukon Gem Purple Majesty How to Hill Potatoes When your indeterminate potato plants are 8-10 inches tall, it’s time to start hilling. Loosen the soil along your rows and with a digging fork pull dirt up on both sides of the potato plant until only the top half is exposed. Be sure that they are hilled on a regular basis before they get to the flowering stage so lots of potato tubers can form along the stem. How Often to Water Potato Plants Consistent moisture is key in growing potatoes. They require 1-2 inches of water a week and will not do well with too much water. In my hot, humid climate, I prefer to water my determinate potatoes at the base of the plants so fungal diseases aren’t encouraged. Many potato growers use a drip irrigation system. However, there are many successful potato growers who use overhead watering as well. Fertilization Requirements for the Growing Season Potatoes will do best with a soil pH of 6.0-6.5 but can tolerate the pH being a little lower. Always have your soil tested before adding soil amendments, ideally several weeks before planting. There are home soil test kits that test for pH and NPK. Our friends, over at Hoss Tools have a recommended fertilizer schedule that you may want to follow. 1 Week Before Planting- After adjusting soil pH to 6.0 – 6.5, mix 1 1/2 cups per 10 ft. of row of Hoss Complete Organic Fertilizer with your soil. 2 Weeks After Planting- Sidedress 1/2 – 1 cup of Hoss Calcium Nitrate Fertilizer per 10 ft. of row. 2 Weeks Later- Sidedress 1/2 – 1 cup of Hoss Calcium Nitrate Fertilizer per 10 ft. of row. 1 Week Later For 4 Consecutive Weeks- Sidedress 2 cups Hoss Complete Organic Fertilizer per 10 ft. of row. What’s the Significance of a Potato Flower? The plant flowers are a sign of a healthy, mature potato plant that is producing potatoes. Often at this stage, you can harvest baby, or new potatoes but most home gardeners leave the potatoes to grow full size. Potatoes are ready for harvest once the plant starts dying back and turning yellow. Harvest Time for Potatoes While digging up all those mature potatoes may seem like a good bit of work, it is also a good bit of fun. Moving the soil and uncovering those potatoes is like digging buried treasure. Waiting until those potato plants are yellow and dying is the perfect time to get digging. Curing & Storing Potatoes For long term storage, potatoes must be cured. Curing potatoes before you put them up helps their skin thicken a bit, which keeps bacteria out, so they will keep from rotting longer. Simply lay them out in a single layer in a cool, dry place out of direct sunlight for a couple weeks. After that, your potatoes are ready to be put up. They will last the longest when stored in a dark, cool place. Problems You May Have When Growing Potatoes Just like any other crop that you grow in the vegetable garden, potatoes can come with their fare share of problems. There are pests and diseases that can overrun your potatoes if left unchecked. Always be sure to follow label directions when using any product to treat pests or diseases on your vegetable plants. Common Pests of Potato Plants The Flea Beetle, Colorado Potato Beetles, Leaf Hopper, and Potato Tuber Moth are all pests you need to be on the lookout for when growing potatoes. Luckily, there are organic pest control measures, like Neem Oil, that you can use to control the Flea Beetle and Leaf Hopper. The Colorado Potato Beetles and Tuber Moths may require something a little more serious like Bug Buster II from Hoss Tools. Common Diseases of Potato Plants Early blight and late blight are a common soil borne fungal issue with potatoes, especially in high humidity areas. It can be treated with a good copper fungicide. Bacterial wilt and common scab are also common with growing potatoes. Too much water is often a cause of wilt and scab. Practicing good crop rotation will also help keep these problems in check. How Often to Water Potato Plants Now that we know all about growing potatoes and how often to water potato plants let’s get busy prepping those garden beds. It’s almost time to put those seed potatoes in. You may also enjoy reading How to Trellis Tomatoes Like A Pro Happy Homesteading & Potato Growing, Jenny @ The GrahamStead Family Farm Jenny and her family have been homesteading for over 20 years. They are currently farming on their 10 acre Florida farm, that they built from the ground up, 8 years ago, growing 100% of their meat and a lot of their vegetables. From their small herd of Aberdeen Angus Cattle, Pastured Poultry, Sheep, and seasonal pigs, they are able to raise enough meat for the family while selling extra to the community. All the while, striving to butcher at home, as much as possible, and use the bits and pieces of their harvest by preserving food, making bone broth, and (Jenny’s favorite) tanning all kinds of hides! Sources: https://growhoss.com/blogs/growing-guides/potato?_pos=1&_sid=19a72d180&_ss=r https://www.montana.edu/extension/valley/potatoguide.html Potatoes in the Home Garden – 7.617 Gardening Homesteading