How do I sew / repair chair that is split along a seam?

Chair is split along a seam where a cushion meets.  What type of stitch hols firmly?  I plan to hand sew this with upholstery thread.

Comments

[RavingMadStudios]

That kind of depends on the chair, and how the split happened (i.e. did the existing seam just come undone, or did the fabric tear along the seam line?), and where the split is on the chair. I don't suppose you could post a picture? That would really help a lot.

[pgarland]

Sorry I do not have a picture.  It appears that the existing seam came apart due to weakening of thread.  The thread is broken and the split is now about 8-10 inches in length along the seam.

I have purchased upholstery thread and assume I can try to blind stitch this by hand; but will it hold?
 

[RavingMadStudios]

The blind stitch is going to be iffy, especially if the area has to withstand being sat upon. I personally wouldn't risk it.
It's not going to be quite as nice looking, but I'd go with a whip stitch and a curved upholstery needle if I were you.