SAM
Well-Known Member
Did anyone start yet? After nine seasons with the raised bed garden, this is definitely a repair / rebuild year for me.
Now that temps on average are getting warmer earlier and we're classified as Zone 7a in my area (was Zone 6b before Nov 2023), I wanted to try starting seedlings indoors two weeks earlier than I have been in the past.
I have two 4 ft grow light fixtures, each with eight T5 fluorescent bulbs, that I bought in 2018. Fired one up on March 3rd to start some seedlings and three of the bulbs were out. So, I switched in some good bulbs from the other fixture and went down the rabbit hole shopping for replacement 4 ft T5 bulbs. Long story short, I bought some LED grow lights made to fit a T5 fixture and replaced all eight T5 fluorescent bulbs with LED. Expensive, but maybe I'll save some on electricity with the LED bulbs.
The LEDs arrived just in time because another fluorescent bulb burned out while they were shipping.
Here's an LED in place of the burned out fluorescent bulb. I thought, uh oh, maybe these LEDs won't be as bright because I'm losing the reflection of the fluorescent bulbs off the fixture.
Not so, with all eight LED bulbs installed, the light is intensely bright.
So, worried about the amount of light, I nerded out completely and got a PAR meter. Photosynthetically Active Radiation meter measures the intensity of light in the 400 and 700 nanometer range important for photosynthesis. Units of PAR are in micromoles/sec/m², believe it or not. I read seedlings should get between 300 - 500 PAR optimally.
These LEDs are pretty intense with ~ 400 PAR dead center. A little high, so I raised the light up a little and got it down to about 300.
Anyway, results were good, better than previous years with the fluorescent bulbs. Seedlings on Mar 28:
The other repair / rebuild this year is the rotted out raised bed boxes. That's another story I'll post later...
Now that temps on average are getting warmer earlier and we're classified as Zone 7a in my area (was Zone 6b before Nov 2023), I wanted to try starting seedlings indoors two weeks earlier than I have been in the past.
I have two 4 ft grow light fixtures, each with eight T5 fluorescent bulbs, that I bought in 2018. Fired one up on March 3rd to start some seedlings and three of the bulbs were out. So, I switched in some good bulbs from the other fixture and went down the rabbit hole shopping for replacement 4 ft T5 bulbs. Long story short, I bought some LED grow lights made to fit a T5 fixture and replaced all eight T5 fluorescent bulbs with LED. Expensive, but maybe I'll save some on electricity with the LED bulbs.
The LEDs arrived just in time because another fluorescent bulb burned out while they were shipping.
Here's an LED in place of the burned out fluorescent bulb. I thought, uh oh, maybe these LEDs won't be as bright because I'm losing the reflection of the fluorescent bulbs off the fixture.
Not so, with all eight LED bulbs installed, the light is intensely bright.
So, worried about the amount of light, I nerded out completely and got a PAR meter. Photosynthetically Active Radiation meter measures the intensity of light in the 400 and 700 nanometer range important for photosynthesis. Units of PAR are in micromoles/sec/m², believe it or not. I read seedlings should get between 300 - 500 PAR optimally.
These LEDs are pretty intense with ~ 400 PAR dead center. A little high, so I raised the light up a little and got it down to about 300.
Anyway, results were good, better than previous years with the fluorescent bulbs. Seedlings on Mar 28:
The other repair / rebuild this year is the rotted out raised bed boxes. That's another story I'll post later...
