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0 pointstuatoru1y ago0 comments

I was told that water beads on leaf surfaces act as lenses, creating burnt spots on the leaves. So water at night.

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mapt1y ago

This is 99% urban legend. You can just barely create it in a lab with just the right plant (with thick hydrophobic trichromes) under just the right light with no wind... but that's not what happens in nature.

tzot1y ago

> but that's not what happens in nature.

Exactly. When it rains in nature, 95% of the times a) there isn't enough sunlight for the droplets to focus and make a burn spot, and b) the droplets don't stay on the leaf but flow down instead.

The original advice is solid and not an urban legend, but it applies to cases like watering plants in your balcony when the sun is out, bright and hot. Source: I have caused burn spots in plants of my own.

Kerrick1y ago

Those “burn spots” are almost certainly from a fungal disease, not from some magnifying glass effect. https://s3.wp.wsu.edu/uploads/sites/403/2015/03/leaf-scorch....

rvense1y ago

I was told to water at night because it doesn't make much sense to pour water on the ground only for it to evaporate before it goes where it's needed.

lukas0991y ago

I believe watering at night will generally lead to more fungal rot problems. Better to water early morning, when the water will have a chance to sink into the soil, but will be pulled up into the plant by evaporation of water from the leaves (the leaves’ own water, not water you applied)

weweweoo1y ago

Well, that obviously depends from how sunny and warm it is.

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