As I mentioned in another thread I have been growing Afghanis from seed for some years. Many people think Afghanistan as a hot dry desert. When in actuality it is some areas, but with the mountains spread all over the climate can very largely. The daily temperature swing is widespread and typically 30c variation between day and night. in the more mild lower mountainous area were our plats likely would be able to grow temps can be as low as 60 at night and highs in the upper 90 during the summer growing months. precipitation is higher in spring and tapers down to almost nothing threw the summer months and picks up again in Aug.
With all that in mind I grow mine in its own little climate separate from my other plants. As seedlings I give them plenty of water for the first 30-40 days of veg and taper down to an every 3rd or 4th day watering with about 10% drain off. Seedling get mild temps 50 night and 75 day with RH around 60-70. Once they are well into there veg around day 30-40 I taper the RH down to 20-30 and bring the temps upto 65 night and 85-90 day letting the soils dry out for sometimes as much as 4-5 days between watering. About the 40-60 day mark they still look lanky never really filling out like my other plants. Flip them to 12/12 still on a higher N feed for the first 10-14 days of 12/12 then I change up the feed for bloom. They seam to not like anything but some basic neuts and cal/mag. I use SensiGrow/Bloom A+B and GH
CaliMagic 1-0-0.
Its not till the 60-70 day mark that I start rampping up the RH to 50-70 and water them every 3rd day. pushing closer to the 90 day mark they will explode with buds and fill out for the last 14-21 days.
Just my experience with them and it works well for mine. I don't worry about the extra long grow season and just let them do there thing. mostly my plants will get 6-7 feet tall and have lots of cola sites that fill out rather well. You just have to give them time.
All my other plants grow with 6-8 weeks veg and 6-8 weeks flower. These however are always still in there little solo condo well past my other harvest to the point your are totally off cycle. I never had luck trying to grow them side by side my white rhino.