Flowering: When to switch from Metal Halide to High Pressure Sodium

[RickyRicardo]

Hello, I grow in a BloomBox from BC Northern Lights. So I have significant height restrictions.

I have started my current flowering phase with a 400W Metal Halide, I am about to complete my second week.

First thing I notice is how minimal the stretching has been compared to my last grow with a HPS.

I am wondering why I should switch to HPS, at the start of the 3 week or the start of the fourth week? Or if there is any indications of when in the flowering phase the big part of the stretching is over?

Anyone has experience playing with the number of week on Halide and the impact on stretching and bud production?

 

[jammie]

hey ricky- i've found continueing the mh for the first 10-14 days of 12/12 helps minimize stretch. i usually do a flush and change over to flowering nutes at the same time i switch to hps

 

[smokeydav]

In my limited education thus far I have also learned the flush at the light change is a good practice. Glad to see it said again, lots of opinions out there, hard to pick through.