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Potato plants are less than 4 weeks old and they are growing as if on steroids. The leaves are really small and look rather miserable. I read potatoes don't get taller than 60cm, mine are already 95cm and beyond. Now they are starting to fall over, one by one. I don't know what to do.

The plant completely fell over, it's the 5th plant already:

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This one is about to fall over:

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At current growth speed this one will reach 100cm by tomorrow morning. I had to stabilise it with a piece of wood because all of the stems were bent to the floor:

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I thought this was supposed to be easy? Do my plants need an exorcist?

Earth specs:

  • Ph 7.2
  • 200mg/l Nitrogen
  • 170mg/l Phosphate
  • 950mg/l Potassium

I water them thoroughly as soon as the top 5cm dried up which is around once ever 4-5 days.

AzulShiva
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3 Answers3

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What you are looking at here is called etiolation: plants that look like they were stretched out of proportion, with smaller leaves and often pale. The cause is clearly insufficient light. So if you see no option to supply more light (and getting them outside would be the easiest way), they will continue to suffer and slowly die. And don’t expect a “harvest”. The new potatoes are first and foremost storage organs where the plants collect what they could produce from photosynthesis - which, again, needs light (= energy).

Stephie
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  • I thought potatoes can grow in the shade. They are right next to large windows and it was sunny for 3 weeks straight. Should I try wrapping around them with aluminium foil? – AzulShiva May 14 '18 at 09:26
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    @AzulShiva no, unless you live somewhere excessively hot or cold, getting them outside is your best option. Alternatively, set up grow lamps. – Stephie May 14 '18 at 09:28
  • And you may want to look into potato planting alternatives like those tall cages where you could actually bury at least parts of the long stems. But that’s beyond the scope of this question. – Stephie May 14 '18 at 09:30
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    In shade yes, but look your windows: it is small and not near the potatoes. (think how many windows you must have near you potatoes to have full sun, my estimates will be more than 10 windows). So you will have less than 1/10 of light. Additionally, it is just on side, so still weak sun. So you are in very deep shadow. Move few of them really near the glass of window. – Giacomo Catenazzi May 14 '18 at 10:08
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    A few more remarks: 1. Windows won’t let all light pass through: Some is absorbed, some reflected. If you have double glazing, you actually have four surfaces where light is reflected. 2. Vertical windows and vertical sunlight means the light won’t pass through straight, but the light that reaches your plant is likely just reflected light, so less strong than direct sunlight. And the sun will directly hit your windows only a very short time during the day. – Stephie May 14 '18 at 10:31
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    3. The light intensity decreases squared, so a plant that is twice as far from a window compared to another will get only a quarter of the light the other gets. – Stephie May 14 '18 at 10:34
  • http://www.bilder-upload.eu/show.php?file=1c75ca-1526299040.jpg I did some modifications and added a net to catch the stems which will eventually all fall over. Hopefully they can grow closer to the window now. – AzulShiva May 14 '18 at 11:57
  • I have just painfully realized that I can no longer open the windows anymore and water the sunflowers on the ledge... fml – AzulShiva May 14 '18 at 11:58
  • Hi Stephie! I think it would be helpful to copy the two comments you wrote with your "few more remarks" into your answer. Even though they were part of a discussion after the fact, they seem educational and informative. I didn't want to do it in case you didn't think it appropriate! – Sue Saddest Farewell TGO GL May 14 '18 at 19:40
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The soil is too warm, and not enough light. I grew the usual vegetables ( tomatoes, etc) in a cool garage ( roughly 55 F) with a lot of artificial light and they were full and stocky. I sprouted seeds at temperatures like 80 F. I never bothered starting potatoes because they are so easy to bury directly in the garden.

blacksmith37
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It’s to rich in fertilizer I had the same problem and mine are outdoors so it’s not the shade. The soil is to rich most likely in nitrogen

Austin James
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