Should my skin graft on my nose turn black after mohs surgery?

Moh’s surgery on the face often requires surgical repair and reconstruction to reapproximate the skin edges. Flaps or direct closure techniques are used. It is important that you optimize scar healing during this phase in order to reduce longterm scars. For red scars, we use Vbeam laser, followed by fractional laser for scar topography and contour. We recommend Plato’s Scar Serum twice daily for the immediate postoperative period. Fractional laser is safe for scar laser therapy.
There are treatments for swelling and edema of the scars. If there is residual sutures or edema, we advise you to follow a scar treatment protocol that can minimize the time to recovery. Our office specializes in scar revisions for Moh’s surgery.
Best,
Dr. Karamanoukian
Realself100 Surgeon

Thanks for your question. 
Sometimes skin grafts can darken especially if they don't completely take. Depending on the type of graft use, the area can still heal well if properly managed. I would recommend following up with your surgeon so he/she can closely monitor it and use topical medications as needed. Best of Luck

Best to post some photos for an informed opinion. The concern with a black graft is that the graft has not taken and best to see your PS for reassurance. 

Sometimes skin grafts are the very best option...depending on the size and location of the hole.  However, skin grafts are often not our first choice for many reasons (i.e. mismatch with surrounding skin, slower healing, fragile nature of grafts, and a needed "donor site").
Skin grafts are almost always ugly early on, especially the first 2-3 weeks.  However, a black skin graft can be a bad sign.  #1 Sometimes grafts look black simply because there is a layer of dried blood on the surface.  Very careful cleaning of the dried blood (by your doctor/nurse) may reveal a healthy graft underneath.  #2 Sometimes grafts are a little dark and dusky looking the first few days while awaiting ingrowth of a better blood supply.  #3 But, if the graft is completely black after several days, this usually indicates that some of the skin graft has died.  Sometimes the loss is limited to the upper layers of the skin ("superficial epidermolysis") and sometimes it involves the entire thickness of the graft ("full thickness necrosis").  
In most circumstances, the best option is to be patient because the wound will often fill in from underneath and from the sides.  Even if some of the skin graft has died, it can act as a "biologic" dressing while the wound heals.  Less often, it may be advised by your doctor to removed the graft and either allow the wound to heal or proceed with an alternate procedure.  Healing may take 6 weeks or more.  After 6-7 weeks a logical decision can usually be made as to whether a revision procedure should be performed.
The loss of a skin graft is an unfortunate reality that is NOT necessarily due to surgeon error.  Skin grafts are delicate...skin that has been completely separated and then reattached to the human body.  The skin graft no longer has blood vessels directly supplying the oxygen and nutrients needed to survive.  Instead, the grafts undergo a vital 3-step process allowing survival and eventual reestablishment of a reliable blood supply (the 3 stages are referred to as "diffusion", "inosculation", and finally "revascularization").  Unfortunately, skin graft healing can be disrupted when bleeding, infection, or "sheer" forces do not allow oxygen and nutrients to sustain the graft.  Also, the underlying body area may have a poor blood supply due to the location (i.e. lower legs and feet) or due to other treatments (i.e. radiation treatments, scar tissue or steroids).