Tomatoes and potatoes are in the same family: the Nightshades or Solanaceae. When you dig potatoes, you find edible tubers. On the other hand, tomatoes have fruit that you can eat on the leafy part of the plant. Occasionally, however, gardeners will notice tomato looking things on potato plants. The reasons why potato plants flower are environmental and do not affect the edible nature of the tubers. If your potato plant flowers, you might even be able to grow a real potato plant, which is different from the parent plant in many ways.
It’s not uncommon for gardeners to be taken aback when they spot small, round, green tomato-like fruits growing on their potato plants. At first glance, it seems impossible – tomatoes and potatoes are completely different vegetables, right? Not quite! While we typically grow them for different edible parts – tomatoes for their fruit and potatoes for their underground tubers – both plants actually belong to the nightshade family Solanaceae. This means they share a close genetic relationship and some morphological similarities.
Why Don’t We See Potato Fruits More Often?
If potato plants are capable of growing fruits similar to tomatoes why don’t we see it more regularly in vegetable gardens? There are a few key reasons
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Many potato varieties do not flower or produce fruits even under normal growing conditions, Early and late maturing varieties are less likely to blossom and fruit
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Some varieties may bloom but have male sterile flowers, meaning they do not produce viable pollen. Without pollen transfer from another potato variety, fruits will not form.
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Even when a potato plant flowers and pollination occurs, the right environmental conditions are still required for successful fruit formation. Cool, humid summers replicate the native Andean mountain climate of the potato and encourage fruiting. Hot, dry weather inhibits it.
So in most home gardens, the average potato plant simply does not receive the proper cues to initiate fruit production. When it does occur, it’s a rare and interesting novelty for the gardener!
What Do Potato Fruits Look Like?
The tomato-like fruits that occasionally develop on potatoes are more accurately described as berry-like. They are small, green, and round or oval in shape, resembling a tiny green cherry tomato. Some varieties may produce fruits with a purple skin. The fruits contain small edible seeds, just like a tomato.
They typically develop after flowering and pollination occurs on the potato plant. The flowers and pollination requirements are very similar between potatoes and tomatoes since they are close relatives. This helps explain why the fruits look so similar!
Are Potato Fruits Edible?
Here is an important warning about potato fruits – despite appearances, they should not be eaten!
While the underground tubers are an edible vegetable, above ground potato plant parts such as stems, leaves, and fruits contain high concentrations of dangerous glycoalkaloids such as solanine. This natural toxin can cause gastrointestinal and neurological issues if ingested, even in small amounts.
So while the green fruits may look tempting, it’s best to leave them alone and stick to enjoying potatoes the traditional way. Curiosity is not worth risking illness!
Can You Grow Potatoes from Potato Fruit Seeds?
Since the fruits contain ripe seeds, an interesting gardening project is to try growing new potato plants from them. Here are some tips if you’d like to give it a try:
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Allow fruits to fully ripen on the plant – they will change color and soften when ready.
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Extract and dry the seeds from ripe fruits. Store in a cool, dry place.
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In spring, sow seeds indoors in seed trays just like you would tomato seeds. Provide warm soil temperatures and plenty of light.
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Transplant seedlings to the garden once frost risk has passed. Hill and care for them as you would standard potato plants.
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Tubers will form on mature plants in late summer, ready for harvest.
The fun of growing potatoes from true seeds is observing the diversity of tubers that develop. Potato plants grown from tubers are clones while seed-grown plants introduce genetic diversity and new traits. Tuber appearance, quality, and flavor will vary!
The Takeaway
While uncommon, potato plants can sometimes produce fruits that resemble small green tomatoes. This occurs as a result of the close genetic relationship between potatoes and tomatoes as fellow nightshade family members. The fruits themselves are not suitable for eating, but can be used to generate new and unique potato plants. So if you notice some odd little fruits on your potato plant this year, no need to be alarmed – just enjoy this unique garden curiosity!
Do Potato Plants Bloom?
Potato plants produce flowers during the end of their growing season. These turn into the true fruit of the plant, which resemble small, green tomatoes. It’s normal for potato plants to flower, but the flowers usually just dry out and fall off without making fruit. Why potato plants flower can depend upon the temperatures or excessive amounts of fertilizer. Plants that experience cold, nighttime temperatures will set fruit. Also, high amounts of fertilizer can encourage the formation of tomato looking things on potato plants.
Tomato Looking Things on Potato Plants
Can a potato plant grow a tomato? The fruits that look like tomatoes are actually just potato plant berries. The berries are not edible but they dont affect the development of the tubers. Fruit doesn’t hurt the tubers’ growth, but kids can get very interested in the little fruits, which can be dangerous. Where potato plants turned into tomatoes, the fruits create additional interest to the leafy greens. That said, nightshade plants have high levels of a toxin called solanine. This is a poisonous substance that can cause illness in people, especially children. When kids are playing, it’s best to keep the fruit and other tempting things out of their reach. The fruits resemblance to sweet cherry tomatoes can pose a hazard to little ones.
How I Grew Potatoes And Tomatoes On The Same Plant
Can a tomato plant grow on a potato plant?
A pomato plant, sometimes referred to as a “half potato half tomato” plant, is the result of grafting a tomato plant (the scion) onto a potato plant (the rootstock). This unique hybrid grows tomatoes above ground and potatoes below ground. How do I graft a tomato plant onto a potato plant?
Can tomatoes and potatoes grow together?
If you are considering growing tomatoes and potatoes in the same garden together, there are a few factors you’ll need to consider. While both of these plants are quite popular in many amateur vegetable gardens, do they make good companion plants when grown alongside one another? Read on and find out if you should grow these plants side by side!
Can you plant Tomatoes next to potatoes?
It seems logical that you could plant tomato plants next to potatoes since they are in the same family. It is okay to plant tomatoes near potatoes. The operative word here is “near.” Since both tomatoes and potatoes are in the same family, they are also susceptible to some of the same diseases.
How do you grow tomatoes & potatoes?
Start with a healthy plant and make sure it gets ample water and sunlight, and chances are good you’ll have a nice harvest of some tomatoes and potatoes! Look for a planting location in full sun that gets a minimum of 6-8 hours of direct sunlight per day. Also, make sure you’re close to a water source to make watering the plant easy.