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The Surprising Impact of Seed Potato Size on Your Potato Yield

Hello, fellow growers and gardening enthusiasts! Welcome back to another informative post on Today, we’re going to explore the fascinating world of seed potatoes and how their size can impact the overall yield of your potato crop. There are several factors that contribute to the final yield, and while it might seem logical that larger seed potatoes would produce bigger yields, it’s not always that straightforward. So, let’s dig a little deeper and discover the truth behind seed potato size and its influence on potato yields.

Size of the seed potato

It’s no secret that larger seed potatoes have more stored energy and nutrients, which can lead to more vigorous growth and potentially higher yields. However, this advantage can diminish if the seed potato is too large, as it may be more susceptible to rot or disease. Striking the right balance between size and health is essential to ensure a bountiful harvest..

The number of eyes or sprouts

Each “eye” on a seed potato has the potential to grow into a new plant. Larger seed potatoes typically have more eyes and can produce more shoots, which may result in more potatoes. However, overcrowding can lead to smaller potatoes, so it’s important to ensure proper spacing between plants.

How many sprouts grow on a large potato compared to a small potato?

The number of sprouts, or “eyes,” on a potato can vary depending on the size, variety, and growing conditions of the tuber. Generally, larger potatoes have more eyes than smaller ones. However, it’s important to note that the number of eyes is not solely determined by the size of the potato.

On average, a small potato may have around 4-6 eyes, while a larger potato can have 8-12 or even more eyes. Some potato varieties naturally have more eyes than others, regardless of their size. The age of the potato and its storage conditions can also affect the number of sprouts that develop from the eyes.

When using seed potatoes for planting, it’s crucial to ensure that each piece has at least one healthy eye. This will ensure that a new plant can grow from each planted seed potato. Keep in mind that having too many sprouts on a seed potato can lead to overcrowding and competition for nutrients, potentially resulting in smaller tubers. This means you need to space large seed potatoes 3-4 inches further apart than standard small seed potatoes.

Soil fertility and quality

High-quality, free-draining soil that is rich in nutrients is crucial for producing a good yield of potatoes. If the soil is lacking in nutrients or is too compacted, even a large seed potato may produce a disappointing yield. To achieve the best results, make sure to test your soil and amend it with organic matter like compost or well-rotted manure if necessary.

Weather and growing conditions

Temperature, sunlight, and moisture all play a significant role in potato growth. If conditions are unfavorable, the overall yield may be lower, regardless of the size of the seed potato. To ensure optimal growing conditions, plant your potatoes during the recommended planting window for your region and monitor soil moisture levels throughout the growing season. Keep an eye on your local weather report for up-to-date weather information and conditions.

Pest and disease management:

Pests and diseases can significantly reduce potato yields. Proper pest management and disease prevention are important for ensuring a healthy crop, no matter the size of the seed potato. Some common pests and diseases that affect potatoes include Colorado potato beetles, aphids, and late blight. To learn more about preventing and treating these common issues, check out our upcoming comprehensive guide on Potato Pest and Disease Management.

Why do larger seed potatoes rot more easily than small seed potatoes?

Larger seed potatoes may rot more easily than smaller ones for a few reasons:

  1. Surface area and moisture: Larger seed potatoes have a greater surface area, which means more opportunities for moisture to be absorbed into the tuber. Excess moisture can create an environment conducive to the growth of fungi and bacteria that cause rot.
  2. More eyes and wounds: Larger seed potatoes often have more eyes, which are the growth points for new shoots. Each eye represents a potential entry point for pathogens, increasing the risk of rot. Additionally, larger tubers may have more wounds or damage from handling, providing further access points for rot-causing organisms.
  3. Energy reserves: Larger seed potatoes have more energy reserves, making them more attractive to pests and pathogens. In some cases, this can lead to a higher risk of infection and rot.

To minimize the risk of rot when using larger seed potatoes, follow these guidelines:

  • Select certified, disease-free seed potatoes.
  • Handle seed potatoes gently to avoid bruising or wounding.
  • Store seed potatoes in a cool, dark, and well-ventilated environment to minimize the risk of rot.
  • Plant seed potatoes in free-draining soil and avoid overwatering to prevent the growth of fungi and bacteria that cause rot.


In conclusion, while larger seed potatoes can potentially produce a bigger yield, due to them usually having more eyes for sprouts and the potato itself is a larger store of energy for growth compared to a small potato, large potatoes have their drawbacks when it comes to disease and difficulty planting. Other important factors like growing conditions, soil quality, and pest management, all have a major influence on the outcome of the crop. Proper care and attention to all of these factors are essential for maximizing potato yield.

From my experience, I use industry standard-sized seed potatoes, which are 1 1/2″ to 2 1/2″ or 40mm to 60mm in size. Going much smaller or larger than this will probably begin to have negative effects on the crop.