Root vegetables like potato need loose and stone free soil.
If you’re growing potatoes in a container, then knowing how much depth do potato plants need to grow will help you to choose the right container.
Depending on potato varieties, you must determine how deep do potato roots grow.
Potato roots grow up-to 18 inches deep from the surface of the soil. But, the productive part i.e. tubers are available at 10-12 inches from the top soil.
Spacing between potato plants must be 12 inches and 36 inches far apart between rows.
This is why you must grow root vegetable in loose soil, so that growth of tubers is not restricted.
Deep rooting is a sign of healthy plant.
Avoid planting potato in soil that compact when watered and acts as a barrier for roots.
Without complete knowledge about root system, you can grow potatoes successfully.
Also Read: How much water does potato plant need?
Important of Roots and Potato Root System
Roots are responsible to uptake water, dissolved minerals and nutrients. Apart from this, they anchor the plant and save it from external stress like wind.
Similarly, deep roots are responsible to reach water resources and nutrients at deeper levels. Deeply rooted plants are anchored strongly when compared to shallow rooted plants.
To increase potato yield, you must understand potato root system.
Potato roots system is determined fibrous root system that doesn’t reach deeper levels of the soil. This means you must consistently water your plant to keep it healthy.
However, the main root of potato plant reach 18-20 inches deep while the edible part i.e. the tuber can be found 10-12 inches from the surface of the soil.
Fibrous root system of this vegetable plant can’t tolerate drought situation.
If you’re planning to grow potatoes in a container, then ensure the potting soil is loose and well-drained. Also, size of container should be more than 16 inches.
Don’t go for small containers, your plant may experience root bound and stunted growth.
How Deep Do Potato Roots Grow?
Knowing how much depth roots grow, will allow you to prepare ground accordingly.
As mentioned already, potato roots reach up to 18 inches depth. It may vary depending on the variety you choose.
Not just depth, you should also consider how much space do potato needs to grow.
Fibrous root system of potatoes needs room or space to grow. When roots of one plant get tangled with roots of another plant, then growth of one of them will be stopped.
To avoid this, space of 12 inches must be given between plants and 36 inches of space between rows.
Check this out: How to store potatoes after harvest?
Raised Bed or In Ground Soil – Which is better for potato plants?
When roots get an obstacle like hard ground or rock, it doesn’t go well with them.
This is why experts recommend digging 12 inches of ground and add some loose soil to it.
Instead, of this you can plan for raised beds.
When compared to in ground soil, raised beds is best choice for growing potatoes.
- You’ll have complete control on the soil.
- It’s easy to monitor plant on raised bed.
- Can avoid weed growth.
- Easy to harvest.
- Growing soil will be well-drained and loose as plant needs.
- Easy to fertilize raised bed.
- Experts from Cornell University suggest to raised beds, as you can add required amount of fertilizers and organic matter to the growing medium.
Note: You can dig 2-3 inches deep before planning for raised beds. If in case, root out grow raised bed, they will still have loose soil to grow.
This doesn’t mean, you can grow in ground.
Dig 10-12 inches deep soil to remove hard surface and rocks.
Alternatively, you can also grow potatoes in container with 16 inches diameter and more than 16 inches height.
Also Read: How to grow ivy gourd from cuttings?
How deep to plant potato seeds?
Potato roots come out from potato bud and grow downwards, while the stem grows upwards.
So, how deep you plant its seeds also play vital role.
Else, tubers will emerge from the soil and your potatoes will turn green when exposed to light.
To avoid such wastage, plant seed potato 3 inches deep.
This way, roots as mentioned starts to grow downwards and tuber will be formed under the soil protected from sunlight.
When to plant seed potato in the soil?
Potato plants can’t tolerate cold weather. Plant seed potato after last frost, if your region have longer growing season, else you must plant before few weeks of estimated last frost.
Trench or Hilling
Instead of digging deep, some gardeners plan a trench and plant seed potato in it. Depth of these trenches will be 8 inches.
You can also hill up the soil around the conventionally planted seed potatoes, making a depth of 8 inches.
Both the methods are accepted and best to produce quality yield.
Also Read: When and how to harvest potatoes?
What is the best soil for growing potatoes?
Hard and clumsy soil results in deformed tubers.
Raised beds filled with the mixture of garden soil, sand, old compost and organic matter are perfect for potatoes.
Compared to other plants, potatoes need more fertilizer to produce quality tubers.
Use 10-20-10 NPK ratio fertilizers. Nitrogen rich fertilizers will make plant bushy green but the quality of tuber will be degraded.
How to Avoid Root Bound?
When any obstacle stops the potato plant root system growth, root bound will occur.
Yellow or black leaves are signs of root bound.
If you choose small sized container to grow potatoes, this problem arises.
You must repot immediately, else the plant will die.
Check this: Can you grow potatoes in tires?
How to Increase Potato Plant Root Growth?
Strong roots is a sign of healthy plant, as it uptakes more water and nutrients from the soil to make food.
- Use loose aerated growing soil, which allows roots to intake oxygen.
- After every few weeks, check the growing soil and if needed break the soil clumps.
- Provide adequate amount of water.
- Avoid overwatering your potato plant; else it will lead to root rot.
- Phosphorus rich fertilizer will help roots to grow strong.
- Grow potatoes in large container with a drainage hole.
Final Words
Do you think it is important to know how deep your potato plant roots grow?
Yes, it is. Only then you can prepare growing soil.
With fibrous root system, potato plant roots reach up-to 18 inches deep. But, you’ll find tuber 10 inches deep from the surface of the soil.
Don’t take these numbers for granted. Depending on potato variety it may change. How much depth your potato roots grow? Let me know in comments.
Khaja Moinuddin, a computer science graduate, finds joy in gardening and homesteading. Join him on this blog as he shares his experiences in homesteading, gardening, and composting