Red Poison

Has anybody grown this strain and how do I get bigger plants? Theyre around 60cm and this the one in the pics is the troubled one, the barest. I'm on my first grow, all autos, I had a one week delay in getting the tent all set up right and transplanting so they had not ideal situation between week 3 and 4 as they were outgrowing pots and water was too high in ph which has since been rectified. I do absolutely love the colours and the smell ooh wow I could bathe in it lol but theyre tiny in size, I don't smoke but use oil for spinal damage.
I guess I am asking for tips on how to get this particular strain bigger and chunkier the RP is very small compared my other strains and from the diaries I have read and seen, mine seem to be much less abundant with flower but the colours are sensational. Theyre 8 weeks. I struggle to vision the trichomes with a 30x loupe, how long do you think she still has to go? Temps constant 27

I've run a couple of sweet seeds red poison and I agree, beautiful colors and smells during flower. One of my fav "colored" autos.....You didn't mention medium or pot size or lights...of which all are significant in the great scheme of things.
Here's what I do if it's any help...I veg everything, autos and photos under t5ho for 3 weeks, in 2 ltr pots of bio bizz light mix with only DI water when moisture meter indicates h2o need. T5HO are 6500k, 96w. At 3 weeks age, everything is moved to a flower tent of qb+2 cobs (3500K) at 280w, or bout 45w sq ft which runs 12/12 on both autos and photos. When moved, I begin light feeding, increasing as the plant telegraphs need. NEVER overwater or let temps get high and for damn sure, watch ph. A good intake and exhaust setup is essential also. Mine is on a combo of inkbird and acinfinity controlled fans.
With red poison, I topped one and let the other just do it's thing. one formed crown of buds, the other got tall and forced light repositioning but both were around 1.5-1.75 ounce yeild each.
Yours appear to need more time, lil more than 2 weeks I'd guess.