Reduce light during summer?

[Lizgeo]

Several threads from this forum are talking about reducing light during summer time, especially for dends. I have a question on that: do you reduce the length or intensity of light? Naturally, the length of the day light increases in summer (I grow them outside on patio).

I got a couple of dends (Garnet Jewel, Jacqueline Thomas, Little Diamond) that I haven't had any success to bring them to bloom, so I am willing to try something different.

[mtequine]

I notice that I have to move my plants around in the fall and the spring as the intensity of light changes. I have to be careful this time of year that I don't burn leaves of catts and dends sitting in south, east and even southwest windows. Last fall I noticed that I had to shuffle some around to ensure they kept getting enough light.

Hope this helps, I'm sure others will pipe in with more information!

[Gin]

Hi , I think the threads meant to reduce the amount of direct sun because of burn in the summer , not the length . Early is fine but the hot later on will burn them .. Gin

[wetfeet101b]

Reducing light in summer is mainly to compensate for the higher ambient temperatures or lower humidity.

Bright light fuels photosynthesis at a higher rate and this process uses up water at a faster rate than in lower light conditions.
High temperatures causes the plant to evaporate its own water reserves from the leaves to cool it down (transpiration or transevaporation).
Low humidity also triggers the plant to evaporate its own water reserves due to vapor pressure deficiency (VPD). Basically the leaves are trying to match the outside humidity thus expelling its own water reserves.

If a plant dries out too much due to either heat or low humidity, then their cells become more vulnerable to sunburn and thus end up with cellular damage.

So reducing the light in summer is only one option. Other options are
1. Raise the humidity
2. Water more often.