If we are talking about sustaining agriculture, likely not but it wouldn’t be a heat related problem.

Any decent plant growth needs a soil base, and Antarctica’s soil is likely to be incredibly shallow and not bioactive. If you look at places like Iceland and the Scottish Highlands, those places lost a lot of soil as forestry removed the topsoil protection. You would need to implement significant resources into improving very marginal agricultural land.

Also, while the continent is covered in ice, there isn’t much in terms of precipitation.