Potatoes are a delicious part of most gardeners’ diets. They’re tasty no matter how you eat them – baked, fried, mashed, or stuffed, with or without a big pat of butter. And if you know how to care for them correctly to set them up for success, they can be easy to grow in your home garden.
Once they plant potatoes, many gardeners have questions about the best practices for watering potatoes. Like all vegetables in the garden, potatoes do need a regular supply of water throughout the growing season to ensure an abundant harvest.
How and when to water depends a lot on the climate in which you live. In general, most vegetable plants need 1 inch of water per week. I’ve written an extensive article with lots of details on watering your vegetable garden. Here we’ll cover watering potatoes specifically.
As a potato grower, knowing how much water your potato plants need is crucial for a successful harvest. Proper irrigation keeps your potato plants healthy and promotes good tuber development underground. Learning exactly how much water to give your potatoes can seem tricky at first, but it’s easy once you understand the basics. In this article, we’ll cover everything you need to know about potato water requirements so you can grow an abundant crop.
The Key Stages When Potatoes Need Water
Potatoes need varying amounts of water at different growth stages. Here are the key stages to focus on:
Planting To Sprouting
For the first 2-4 weeks after planting seed potatoes, water lightly around 1 inch per week. This encourages roots to grow downward in search of moisture.
Vegetative Growth
Once sprouts appear above ground, increase water to 1.5 inches per week for vigorous foliage growth. This stage lasts around 4 weeks.
Flowering
When potato plants flower, water needs are highest at 2 inches per week. This fuels rapid tuber bulking underground while the plant is flowering.
Maturing
As plants start yellowing and dying back, reduce water to 1-1.5 inches per week Avoid overwatering at this stage, as tubers may rot before harvest.
2-3 Weeks Before Harvest
Stop watering entirely so soils dry out. This toughens skins for better storage. Harvest potatoes once plants are completely dead.
How Much Water Do Potato Plants Need Per Day?
Potatoes need about 1-2 inches of water per week, ideally split into 2-3 deep waterings. For example, if shooting for 2 inches per week, watering 0.5-0.75 inches two or three times weekly is better than frequent light sprinklings. Deep soakings encourage deep roots.
Watering Methods
Drip irrigation or soaker hoses are ideal for watering potatoes. They deliver water directly to the soil without getting foliage wet. Overhead watering wets leaves, which can encourage blight. Hand watering with a wand takes more time but lets you control water at the soil level.
Soil Type Matters
Soil type greatly affects how much water potatoes need
- Sandy soils drain quickly. Potatoes may need water every 2-3 days.
- Clay soils hold more water. Water 1-2 times per week.
- Loamy soils are ideal. Water when top few inches become dry.
Adding organic matter like compost improves moisture retention in sandy soils. amending clay soils improves drainage. Mulching also conserves moisture in the root zone.
Watch For Signs of Under or Overwatering
It’s important to find the right watering balance for your plants. Here are symptoms of too much or too little water:
Underwatering Signs
- Wilting leaves
- Slow growth
- Small or misshapen tubers
- Cracking around stem base
Overwatering Signs
- Wilting leaves
- Fungal diseases
- Rotting tubers
- Fewer blooms
Check soil moisture before watering wilted plants to determine if soils are too wet or too dry. It’s better to underwater than overwater potatoes.
Growing Region Affects Water Needs
Local climate determines how much water potatoes require in different areas:
- Hot and sunny climates demand frequent watering, even daily.
- Cool and cloudy regions need much less, even if rains are infrequent.
- Humid climates with adequate rainfall may only need occasional watering. Use rain gauge to track precipitation.
- Dry climates need diligent watering and mulching.
Adjust according to your climate being careful not to overwater. Extending irrigation scheduling during hot and dry periods.
Container Versus In-Ground Potatoes
Container-grown potatoes need more frequent watering than in-ground plants. Pots and grow bags heat up and dry out faster than garden soil. Monitor soil moisture in containers daily and don’t let plants wilt. Drip irrigation works well for containers.
Stop Watering For Harvest
It’s vital to stop watering potatoes 2-3 weeks before harvesting. This allows skins to thicken for better storage. Wet tubers at harvest are prone to rotting in storage. Allow potato foliage to completely die back before digging. Harvest when soils are dry for easiest cleanup.
Following the right watering schedule at each potato growth stage is key for a robust harvest. Potatoes need ample moisture during flowering and tuber bulking but less watering at planting and harvest time. Adapting your irrigation to soil type, climate, and growing conditions will ensure strong plants and abundant crops. With the right balance of water, your potato plants will thrive!
How to Harvest Potatoes
Potatoes are a great crop because they have pretty clear signs when it’s time to harvest. Eventually, the tops of the plants will start to turn brown and die back. Don’t be concerned! This is a natural part of the potato growing process.
Timing Once the plants completely die, make a note of the date. You’ll want to let the potato cure underground for about two weeks before harvesting. This allows the skins to toughen up so they’re not so tender when you’re digging them up.
You can also stop watering potatoes at this time.
If it’s late in the season, you’ll need to make sure you harvest the potatoes before it frosts or they may get mushy. If you’re coming up on the average date for your first frost and the plants haven’t started to die back yet, chop them down onto the bed to encourage the tubers to harden their skins.
Tools for Harvesting My favorite tool for harvesting is a digging fork. I not only have one, but two digging forks hanging in my garage I love them so much.
I use it for loosening up weeds so I can pull them out by the roots, harvesting carrots, potatoes, and garlic, and breaking up clods of my clay soil before planting. I have this exact one from Fiskars, which is a local Madison company.
Find out more by clicking on the .
Technique This is the point where you have to be very careful! It’s so incredibly easy to spear the potatoes while harvesting. My technique is to stick the digging fork into the soil a few feet away from a dead plant. I use it to gently loosen the soil around the plant and start to sift the soil looking for potatoes.
I’ve never harvested a bed of potatoes without spearing at least a few of them, so don’t get too upset if that happens. You can put them aside to eat sooner than later.
Keep digging around the bed until you think you’ve found most of them. It is hard to get every single one potato out of the garden bed. It’s common the next spring to see new potato plants sprouting out of the garden bed in which they were planted the previous season.
Washing I prefer to wipe my potatoes when harvesting to knock as much soil off of them as possible. If you only have a small amount of potatoes and you think you’ll eat them in the next several weeks, you can wash them off with a hose or in a bowl in your kitchen sink. Let them air dry overnight before moving them into a cabinet or pantry.
If you’ve grown a larger amount of potatoes and you want to store some of them for winter meals, you’ll need to cure them.
What’s the Significance of a Potato Flower?
Potatoes are in the Solanaceae, or nightshade family, along with tomatoes, peppers, tomatillos, and eggplant. Eventually, when your plants have gained significant growth, you’ll notice the plants starting to flower. The flowers can be found on the tips of the plants and range in color from white, to pink, to purple depending on the variety you’ve planted. If you’ve grown other vegetables in the nightshade family, you’ll be able to the similarity between their flowers and potato flowers.
The potato flowers are a sign that the plant has started to produce tubers underground. The bees and other pollinators love making visits for pollen, so you can just leave the flowers for insects to enjoy them.
Sometimes, if the flower is pollinated, it will produce a small fruit that looks like a green tomato. These are poisonous (remember the Deadly Nightshade from Roman Times?) and filled with seeds. Just leave them on the plant and make sure children and pets aren’t picking them.
Usually around the time my potato plants are flowering, I’ve hilled them as much as I can. At this time, I mulch them heavily with hay or straw and continue to make sure they receive 1 inch of water per week until close to harvest time.
How Much Water Do Potatoes Need
FAQ
Do potatoes need to be watered daily?
-
Water Needs:Potatoes need a steady supply of water, typically 1-2 inches per week, which can be provided by rain or irrigation.
-
Watering Frequency:You can achieve this through careful watering, or rainwater harvesting, every three to four days.
-
Soil Moisture:Keep the soil consistently moist, but not soggy, especially during tuber development.
-
Signs of Underwatering:Wilting, dry soil, and cracks and knots on the tubers are signs of underwatering.
-
Signs of Overwatering:Yellowing leaves, soggy soil, and soft roots are signs of overwatering.
-
Soil Type:Depending on your soil type, you may need to adjust watering frequency, especially if you have clay soil which can hold a lot of moisture.
-
Harvest Time:Stop watering about 2-3 weeks before harvest, or when you first see the foliage on the plants starting to turn yellow.
-
Container Growing:If growing potatoes in containers, monitor moisture levels closely, as they can dry out quickly, especially in the hottest part of the summer.
-
Foliage:Due to the dense foliage of potato plants, an adequate amount of water may not reach your tubers, so it’s important to check the soil frequently.
Can you overwater potatoes?
The Consequences of Overwatering
Potatoes prefer a drink, not a flood. Overdo the water, and you’ll be bidding adieu to those precious tubers. Misshapen, rotten, or just plain sad potatoes are often the result of overzealous watering.
Do potatoes like moist or dry soil?
After the tubers have formed they need consistent moisture. If the soil dries out the plants will push a second growth, when water is applied, causing small knobby potatoes and multiples. That said, potato plants should not be kept overly wet or they develop diseases and rot.
When should you stop watering potatoes?
Toughen up potatoes for storage before harvest by not watering them much after mid-August.Feb 6, 2025