Can You Grow Potatoes In A Greenhouse: Unearthing the Secret

As I gazed upon the lush green paradise of my greenhouse, I couldn’t help but wonder: Can I grow potatoes in a greenhouse?

The idea of cultivating these earthy treasures under a sheltered haven of glass and steel sparked my curiosity. It was a quest that led me into a world of experimentation, discovery, and ultimately, a bountiful harvest that defied the conventional norms of potato cultivation.

So, yes you can grow it.

Here are the processes: Potatoes are a cold-season crop that takes 80-100 days to grow from seed to harvest. They like cooler germination temperatures around 40°F and typically sprout in 14-28 days. For best growth, keep the temperature between 65-70°F.

When planting from seed, put them 7-8 inches deep, spacing them 10-12 inches apart in rows that are 36 inches apart. Potato plants can be 18-36 inches tall and wide.

In this guide, we’ll embark on a journey together, exploring the enchanting realm of growing potatoes in a greenhouse. So, let’s dig in and unearth the secrets of greenhouse potato cultivation.

What are The benefits of growing potatoes in a greenhouse?

Extended Growing Season: This method allows you to plant potatoes earlier in the spring and continue harvesting later into the fall. It broadens the potato growing season beyond what’s possible outdoors.

Weather Protection: The controlled environment shields potato plants from adverse weather conditions, such as heavy rain, frost, hail, and wind. This minimizes the risk of crop damage.

Temperature Regulation: You can manage the temperature inside the controlled environment, providing ideal conditions for potato growth. Potatoes thrive in cool to slightly warm temperatures.

Pest and Disease Control: The enclosed space reduces the risk of pests and diseases affecting your potato crop, making it easier to implement effective management practices.

Soil Optimization: You have greater control over soil conditions, including pH levels, moisture content, and nutrient levels, leading to healthier and more productive potato plants.

Higher Yields: Optimal growing conditions and protection from external factors can increase potato yields compared to open-field cultivation.

Quality Assurance: Controlled environments can yield higher-quality and more uniform potato tubers, which is crucial for commercial growers and those seeking premium produce.

Organic Farming: Implementing organic and sustainable farming practices is more manageable in this setting, reducing the need for chemical inputs.

Space Efficiency: Controlled environments maximize space utilization, making it suitable for growers with limited outdoor space.

Customized Harvest Timing: You have the flexibility to time your potato harvests according to your needs, whether it’s for personal consumption or market sales.

How to pick the right variety of potatoes to grow in the greenhouse?

There is a remarkable diversity of potato varieties, with thousands of different types cultivated worldwide. Historically, potatoes have been a staple crop in the Andes, especially in Peru. However, over the past two centuries, they have risen to become one of the world’s leading food crops, finding their way into countless dishes across the globe.

While grocery stores typically stock only a handful of popular potato varieties, such as Russets or Burbanks, growing your own potatoes at home or in a greenhouse opens up a world of possibilities. This presents both an exciting and challenging opportunity for gardeners.

To help simplify your selection process, it’s essential to understand the three primary categories of potatoes and explore some recommended varieties for greenhouse cultivation:

First Early Potatoes:

First early potatoes, often referred to as “new” potatoes, earn their name because they are typically the first to be harvested. These varieties are ideally planted a few weeks before the last average frost date, as they can withstand light frosts. This makes them an excellent choice for greenhouse cultivation, especially in unheated environments.

Also, some favored varieties of first early potatoes suitable for greenhouse growing include Yukon Gold, Dark Red Norland, and Purple Viking.

Second Early Potatoes:

Second early potatoes, also known as mid-season potatoes, take a bit longer to mature compared to their first early counterparts. They are at their peak flavor when freshly harvested, making them an excellent option for year-round home consumption.

In addition, a notable advantage of growing first or second early potatoes is their reduced susceptibility to common potato diseases since they are harvested before diseases can take hold. Recommended second early varieties for greenhouse cultivation include Kennebec, Red Chieftain, and Gold Rush.

Maincrop Potatoes:

Maincrop potatoes, also known as late-season potatoes, require the longest time to mature and produce substantial tubers. Due to their extended growing season, they are well-suited for long-term storage and are frequently found in grocery stores.

Furthermore, they are a viable choice for greenhouse cultivation, especially if you have a short growing season but desire a supply of quality storage potatoes. These varieties excel in baking, mashing, or frying dishes.

How to plant potatoes in a greenhouse?

1. Choose Your Potato Variety:

Select the potato variety that best suits your greenhouse conditions and preferences, as discussed before.

2. Prepare the Potatoes:

Chit your seed potatoes by placing them in a cool, well-lit area for a few weeks before planting. This encourages sprout development.

3. Select Your Container:

Potato Grow Bags:

Use a frost-free greenhouse with daytime temperatures above 10°C.
Fill flexible bags with soil and compost, leaving 3 inches at the top.
Plant potatoes 1 inch deep (1 tuber in a 1-gallon bag, 2-3 in a 5-gallon bag).
As they grow, add soil, leaving 1 inch from the top.
Use high-phosphorus fertilizer.
Harvest some early when the plants flower; wait for the tops to die back for the full harvest.

Raised Beds:

Use a greenhouse-raised bed at least 1 foot high, 3 by 3 feet in size, with 6 hours of sunlight daily.
Add 5 inches of compost mix.
Plant potatoes 3 inches deep, 12 inches apart.
As they grow, cover them with more compost until they reach the top of the bed.
Use nitrogen-rich, partially decomposed compost for added nutrients.

Trenches:

Dig rows in the greenhouse, about 8 inches deep and 6 inches wide, spaced 2 to 3 feet apart. Add organic compost or manure.
Plant potato seed pieces, cut side down, 12 to 14 inches apart, and cover with 3 to 4 inches of soil.
Use potato pieces with at least 2 eyes, about the size of a golf ball.
As sprouts appear (in 12-16 days), add 3 to 4 inches of soil using a hoe, leaving some sprouts exposed. Repeat for several weeks, creating mounds 4 to 5 inches above ground (hilling).
Apply organic mulch between rows after potato plants emerge to retain moisture and prevent weeds.

Containers:

Use containers in the greenhouse for growing potatoes.
Plant 3 seed potatoes in a 24-inch deep, 18-inch wide container. Use 1-gallon bags for one tuber, and 5-gallon bags for 2-3 tubers.
Place containers in a frost-free, warm part of the greenhouse.
Hill potatoes when they reach 8 inches in height, covering them with soil and leaving the top inch exposed.
Repeat hilling when the plant grows about 4 inches above the soil.
Stop hilling when the soil is about an inch below the top of the container.

4. Watering:

Water the potatoes thoroughly after planting to settle the soil and ensure good contact with the seed potatoes.

5. Maintenance:

Maintain consistent moisture levels in the soil throughout the growing season. Greenhouses can get hot, so regular watering may be necessary.
As the potato plants grow, gradually add more soil or growing medium to cover the stems. This encourages the formation of more tubers along the stem.
Keep an eye out for signs of pests or diseases and address them promptly.

6. Harvesting:

Harvest times will vary depending on the potato variety and growing conditions.
For early potatoes, you can start harvesting when the plants flower, typically around 8-10 weeks after planting.
For maincrop potatoes, wait until the foliage starts to yellow and die back. You can then dig up the mature tubers.

7. Storage:

Once harvested, store your potatoes in a cool, dark, and well-ventilated place to prolong their shelf life.

8. Crop Rotation:

To prevent the buildup of pests and diseases in your greenhouse soil, practice crop rotation by planting potatoes in different locations in subsequent years.

Moreover, good companion plants for potatoes are cabbage, corn, chives, cilantro, and leeks. Avoid planting them near tomatoes, eggplants, fennel, pumpkins, and other root vegetables to prevent potential issues

How can I effectively care for potatoes in a greenhouse?

Hilling Up Potato Plants:

Sunlight Protection: Hilling prevents potatoes from exposure to direct sunlight, avoiding the development of harmful green spots caused by the toxin solanine.

Enhanced Harvest: It encourages the growth of additional potatoes along the submerged stem, resulting in a more abundant harvest.

Here’s how to properly hill your potato plants:

Start hilling when your potato plants reach a height of 8-12 inches.
Gradually add soil or compost along both sides of the stem to create a mound.
If you’re growing potatoes in containers, simply add more soil to the pot.
Repeat this process whenever the plants grow at least 4 inches above the soil level.
In containers, continue hilling until you’re within 2 inches of the container’s top.
Hilling also has the added benefits of weed prevention, soil cooling, and moisture retention.
You can reuse the hilled soil in your garden or incorporate it into your compost pile at the end of the growing season.

Watering:

Proper watering is crucial for potatoes. Overwatering can lead to rot, but letting them dry out isn’t ideal either.
Water your potato plants regularly, especially when tubers start forming. Container-grown potatoes may need more frequent watering as they tend to dry out faster than those in raised beds.
Maintain moist, not soggy, soil from the start of sprouting until a few weeks after flowering. Be cautious not to overwater during the first few weeks after planting to prevent rot or disease.
If possible, use rainwater from a barrel, as tap water is often slightly alkaline, while potatoes prefer slightly acidic soil (pH 5-5.5) and may develop scab in more alkaline conditions.

Soil Requirements:

Potatoes thrive in rich soil with organic fertilizer. They are considered heavy feeders.
Aim for slightly acidic soil with a pH between 5 and 5.5. If your soil is more alkaline, potatoes may develop scab.
You can test your soil’s pH at home and adjust it if needed using sulfur or pine needle mulch.
For potatoes with near-perfect skins, consider shredding your compost to create a fine blend, which can improve the quality of your harvest.

Temperature and Ventilation:

Keep the greenhouse temperature within the ideal range for potatoes (above 10°C or 50°F).

Ensure proper ventilation to prevent overheating, especially during hot days.

Fertilization:

Potatoes benefit from regular feeding. Use a balanced fertilizer with a higher potassium content (the third number in N-P-K ratios) to encourage tuber development.
Avoid excessive nitrogen, as it can lead to excessive foliage growth at the expense of tubers.

Pest and Disease Management:

Monitor the plants for signs of pests such as aphids, Colorado potato beetles, or mites, and take appropriate action to control them.
Keep an eye out for common potato diseases like late blight or early blight. Remove infected leaves promptly, and consider using disease-resistant potato varieties.
Practice good crop rotation to reduce the risk of disease buildup in the greenhouse soil.

What are the Common potato pests and diseases?

Common issues when growing potatoes include scabs and unsightly rough patches on the skin caused by high soil pH levels, which can be adjusted if needed.
Potato blight, a potato grower’s nightmare, often occurs after warm, wet weather. In warm, humid greenhouses, watch for signs of blight. Planting early potatoes can reduce the risk, but always use fresh soil and practice crop rotation in raised beds.
Aphids, tiny pests, can harm potato plants by feeding on foliage and transmitting viral diseases. Control infestations with insecticidal soaps or by washing them away with a stream of water.
Colorado potato beetles can be manually removed or become a meal for birds. If their numbers grow, apply organic pesticides at dawn or dusk to avoid harming beneficial insects.

FAQ:

How long do potatoes take to grow in a greenhouse?

Potatoes typically take about 70 to 120 days to grow to maturity in a greenhouse, depending on the potato variety and growing conditions.

Can you chit potatoes in a greenhouse?

Yes, you can chit (pre-sprout) potatoes in a greenhouse. The controlled environment can provide ideal conditions for starting potato sprouts before planting.

At what temperature do potatoes start to grow?

Potatoes begin to grow when the soil temperature reaches around 45 to 50°F (7 to 10°C). Warmer temperatures promote faster growth and sprouting.

Final words

In conclusion, I’ve found that growing potatoes in a greenhouse can be a great idea. At first, I wasn’t sure if it would work, but it turns out it’s quite doable and has some clear advantages.

Moreover, the greenhouse offers protection from harsh weather and pests, which means you can grow potatoes all year round. Plus, you have better control over the environment, like temperature and soil quality, leading to healthier and more productive potato plants.

While setting up a greenhouse can cost a bit upfront, the long-term benefits in terms of a steady supply of fresh potatoes make it a worthwhile investment. Use the method that I mentioned above. So, if you love potatoes, consider giving greenhouse potato growing a try it’s simpler than you might think and very rewarding.