Grow materials shelf life (bulbs, nutes, etc)

[rangerjake]

Long time, back again.

Getting ready to start my 2nd grow in a few weeks after a great learning experience and very successful first go during the summer and fall of 2019.

I have a fair amount of leftover items from round 1 and am curious peoples' thoughts/experiences regarding shelf life while not in use.

I have 2x Philips Mastercolor CDM Elite 315W CMH Agro Lamp T12 - 3100K. Philips seems to say (my reading of their website) that 10% failure rate happens at 12500h. Which is over a year and a half continuous runtime. I used these for about 2250h each, and they have been stored wrapped in soft cotton, dry, and mostly in moderate temps (40f-70f). Think they are good for a second full grow of equal or lesser time (<2250h)?

I also have decent cache of leftover GH Flora series nutes. Likewise stored in cool, dry, dark storage. GH seems to say the Flora series of products is good indefinitely. I'd imagine the mfr. would err to push me into buying new product, so I figure this is safe guidance. But happy to hear thoughts. Think I can carry over GH products that aren't Flora nutes? Cal/Mg, ArmorSI, FloraKleen, Rapid Start, Nectar, Kool Bloom?

Everything else used will be either new or non-diminishing supplies. All for a couple new Nirvana strains (1st grow: Nirvana white widow af, blue mystic, rasp. cough; 2nd grow: Nirvana Critical CBD, Somango XXL, and redoing Blue Mystic because I will be growing in an environment with v cool lights out temps (40-50f) and hoping those temps help to really pop the "blue/purple" coloring).

Thanks all!

[ChadWestport]

You 're correct, bulbs are rated by hours of use. Youseem to have low milage on your bulb, I'd continue to use it. The nutrients, I've never received a good answer or definitive timeline. One concern is the different nutrients falling out of suspension, which would throw the ratios off and possible react negatively with other supplements. For piece of mind, I might pick up some new nutrients but I wouldn't consider it essential.

[SoOrbudgal]

Hi again rangerjake good to see your starting another grow. Can't really comment on the older products if they go bad? So you may have a huge temp flux during lights on and off? May need to supplement heat in that area, i kept a chicken coop clamp light with reflector in my tent on the porch as xtra heat inside the tent used a CFL replaced the red heat lamp.

[rangerjake]

Hi again rangerjake good to see your starting another grow. Can't really comment on the older products if they go bad? So you may have a huge temp flux during lights on and off? May need to supplement heat in that area, i kept a chicken coop clamp light with reflector in my tent on the porch as xtra heat inside the tent used a CFL replaced the red heat lamp.

So here is how I plan to resolve that:

The tent is in a basement which tends to have an ambient temp of around 40-50f. It's not a huge space. In the last grow I noticed about a 10-15f increase in ambient temp under the lights vs. lights off, where the baseline temps tended to be 60-65f. I am no expert on thermodynamics, but I have a hard time reasoning how the ambient temp delta would be different based on a 20-25f lower ambient temp.

This time I am using my exhaust fan but not exhausting air to the outdoors, rather just exhausting air well away from the intake vents of the tent. My hope is that careful adjustment of fan pull will help to create a steady lights on temp of low 60s. And by exhausting air into the same space (800sqft room, hardly airtight) I can marginally raise the ambient temp in the room so there is a slightly reduced ambient temp outside the tent when lights are on.

My plotting here is all theoretical and estimates based on how much heat 2 315w LECs put off. I could be wayyy off. But I don't know where, cause I think I have a fairly good grasp on most of my numbers. Invariably I do have a couple space heaters that can be employed in extreme situations- though the electric draw of those things dwarfs the electric draw of the whole rest of the apparatus combined.

Figuring these little problems out is a fringe fun benefit of the grow process. I am lowkey excited to tinker a way to make this work well.

Thanks for chiming in again, appreciated your inputs last time and look forward to more of your input this time around. Hope you are well.

[SoOrbudgal]

Okie Dokie you know what your doing can't wait to see the starts.

[ChadWestport]

My hope is that careful adjustment of fan pull will help to create a steady lights on temp of low 60s. And by exhausting air into the same space (800sqft room, hardly airtight) I can marginally raise the ambient temp in the room so there is a slightly reduced ambient temp outside the tent when lights are on.

low 60's is going to be on the cold side for lights on. Any temperature drop during lights out would also create problems for the plant and it's root zone.

[rangerjake]

low 60's is going to be on the cold side for lights on. Any temperature drop during lights out would also create problems for the plant and it's root zone.

Hm, well it'll be interesting to find out. The strains I am growing (most of them at least) are cold weather hardy and even if you grow outdoors where I am you're talking about regular temps in core growing season in the 50s, and certainly the 40s into flowering season. With no fan I am sure it'll be mid 60s or above under the lights. I guess the question becomes for a few hours of dark will that effect roots, or conversely, should I run a 24/0 veg cycle and by the time I go to flower in March it'll prob be more consistently 50s on the cool side during dark hours.

If I run a 24/0 (which I have never done, only a 20/4) I have no doubt I'll be able to keep the temp in there really lovely for plants.

[ChadWestport]

Cold temps can effect the roots by making it wetter longer. The plants will transpire less, which means it isn't pulling water up through the plant as fast. Metabolism slows in those temps and this can lead to nutrient uptake issues as well. I have run many veg cycles at 24/0, so I do know that it can and will work if you need to do that.

[rangerjake]

Cold temps can effect the roots by making it wetter longer. The plants will transpire less, which means it isn't pulling water up through the plant as fast. Metabolism slows in those temps and this can lead to nutrient uptake issues as well. I have run many veg cycles at 24/0, so I do know that it can and will work if you need to do that.

That may be the way to go through the colder months.

In a pinch if I get to flowering and its still on the chilly side I bet one or two of these could be a safe, low wattage way to radiate just enough heat around the grow medium and plants to keep things in a comfy-cool range.

https://www.chewy.com/cozy-products-cozy-pet-warmer-radiant/dp/183572