You can undergo a hair transplant at anytime during the year, even in summer. But we advise you to focus more on the postoperative instructions, because they may affect your daily life, even there are less activity restrictions after the procedure.
In summer, especially in the first 7 or 10 days after the hair transplant surgery, you should avoid swimming and your skin should not be exposed to sunlight.
The harmful effects of UV lights on the skin is very well known, especially after a surgery with stitches. But that would not much be the case with the hairy skin of the head.
Even in cold winter days you are not be able to wear a hat or a cap after the procedure, because they may damage the transplanted area on the head and cause hair loss.
The most appropriate time for hair transplant surgery is 3 or 5 days, which you take off from your work and take a break from the daily routines. Whenever you undergo a hair transplantation treatment, it is necessary to consider and follow the medical instructions so that the transplanted area on the head does not get any damage.