I have worked on the design/build of commercial flower and tomato greenhouses and 'hothouses' and now that its legal this.
LED just is not there yet perhaps in 2021. I dont spec lights but they are typically 1000W-1200W HPS of some sort. Gavita is a good manufacturer we have dealt with.
Remember you have to go with the input VA of the ballasts 220.18(B) which can be significantly more than 1k and its a continuous load 210.19(A)(1).
All of the horticultural
lights are typically hung in a cord and plug 'greenhouse style' directly below the receptacles, Take a close look at 210.21(B)(3) and 410.62(C).
UL 1029 and 410.62(C) don't play nice, you might end up with all 20A 240V circuits with 3 lights per ckt, you can theoretically use 30A circuits with four 1k lights per ckt and 15Aor 20A twistlocks per 410.62(C).
*Note the 2020 code is requiring GFCI for horticultural lighting (410.184)*.
If your looking at 3ph or over 112.5 kva of load I have learned to avoid 208 and 277 like the plague 208 just does not have enough punch, 277 the equipment and 70E requirements will price you out.
I do a 240V delta with 'straight' rated two pole breakers, or a 400/230 'euro star' (now used by 89% of the world). The advantage of the delta is you get some 120V and its 'in' the NEC 220.5. The 230V euro star or (415/240) has the advantage of single pole switching and GE at least makes affordable breakers, however 400/230 is non-NEMA (IEC standard) about as common as Plilly two phase so YMMV.
[All references now 2020 NEC]
Cheers