Allotment Gardening Advice Help Chat

Growing => Growing in Greenhouses & Polytunnels => Topic started by: adri on February 03, 2019, 20:40

Title: LEDs how long should they be on?
Post by: adri on February 03, 2019, 20:40

Got some LEDs in the cool greenhouse and they seem to be doing a good job so far.  They are currently on for 16 hours a day.

Baring in mind that some plants are short day and some are long day (and I have a wide mix under the lights) what would be the optimum amount of time to have the LEDs on?  What I'm after at this time of year is vegetative growth.

Any suggestions?

TIA

Adri

Title: Re: LEDs how long should they be on?
Post by: Beloved Porcupine on February 06, 2019, 07:01

Hi,  I just got a copy of Gardening Under Lights (L Halleck), which gives guidance for all types of veg, fruit, flowers, herbs.  For lettuce and rocket, for instance she recc 12 hours (evidently too much would encouage them to flower).  She recc grouping plants by requirement and adjusting light/timing accordingly.   I hope that helps!

Title: Re: LEDs how long should they be on?
Post by: adri on February 06, 2019, 07:37

thx.  will buy the book.

Title: Re: LEDs how long should they be on?
Post by: Beloved Porcupine on February 08, 2019, 13:58

FYI, I got this for less than £2 as an ebook, so not a big outlay of cash

Title: Re: LEDs how long should they be on?
Post by: Aidy on March 13, 2019, 22:15

First question would what is the output of the lights?
On average as I have chillies and toms in my grow tent 12 hours is the norm then I add an hour a week just before I put them in the greenhouse once temps are up
My unit is 300 watt, I have a smaller 16 watt which is used for germination just to give a bit of light as they poke through.