Is swapping from HPS to MH mid veg ok?

As the title suggests, I’m thinking about swapping my HPS with a MH at day 14 of veg. Reason for this is that I was getting light burn on my Amnesia Haze Auto which has turned its leaves a bit yellow and causing canoeing and 45* angle toward the light.
I have since raised the light to 30” which has stopped the angle of the leaves but I still have mild canoeing and yellowing. I noticed last night my Blueberry Auto (11 days old) started to do the 45* angle toward the light. Colour is still green but I’m worried they’re getting too much light for their young age.

Is swapping from HPS to MH a good idea or will this cause more stress? I don’t want to stunt the plants more than I already have. Thanks

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You’re supposed to run the mh during veg and change out to hps during flowering, you should be good changing up, my friend


I’m aware of the bluer spectrum of the MH bulbs which is good for veg but I also know of growers utilising the efficiency of the HPS throughout the whole grow as it produces more lumens per watt.
With mine being autos, I went for the HPS straight off the bat thinking I’d get bigger yields. I had my light too close for a bit though which caused heat stress and light burn.

So my MH is now installed and running so I’ll monitor it over the next few days and see how it goes.


Awsome my friend kerp me updated

They will do much better under HPS. Your damaged leaves will never recover, look at new growth. @Smokin_Duck

Im sorry im more of an outdoor grower didnt mean to guide you the wrong way, its what i was told to use mabye i was mislead into buying two bulbs? @Smokin_Duck @Grandaddy013 to some people its about the mighty dollar, no interest in
Helping you out its more like helping them self thanks grandaddy

MH is for veg HPS is for flower. You need both bulbs. Each one has a specific place. You CAN use the same bulb the entire grow, but it will suffer. If you use HPS for veg, your plants will have a lot of stretch. If you use MH for flower, you will have loose airy buds. Hope this helps

Ok then im guessing i wasn’t misleading @Smokin_Duck i think he stared out with hps for vegg and is changing for hm , , if im correct, i bought my system way back second hand. ive vegged with hm bulbs during winter months to get a head start @Grandaddy013

Leaves have never been super green though but growing slowly. I’ve seen many other growers with much larger plants with dark green leaves at this age. My blueberry has dark green leaves but also very slow grower.
Pic for reference

And yes I was using HPS for a seed to harvest grow but I have swapped to MH for the rest of veg (hopefully more than 4 weeks cause these plants are tiny for their age).

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They looking good for 13 days, some strain grow faster than others imo, good luck buddy

Ok cool. First grow so I’m just judging my progress of others I’ve seen. Other amnesia Haze plants seem much darker and bigger so that’s why I think mine has been stunted.
Just gonna try to keep them alive this grow and see what happens

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Keep us update, imo, they looking good, best wishes on your first grow

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