at the beginning of this act, John Proctor says, It is winter in here yet. Why is this pertinent to what is going on?

Act II of takes place in
spring. John Proctor has been hard at work planting crops and asks Elizabeth to pray for a fair
summer. A few moments later he says:

I think well see
green fields soon. Its warm as blood beneath the clods.

It is not much later, however, that he remarks:

Its winter in here yet.

The immediate occasion
for this comment is the lack of flowers in the house. He says Elizabeth ought to bring some in
and she says she will do so tomorrow. However, the lack of flowers and their terse conversation
about them are merely symptoms of the frostyin the house.

Proctors comment
that it is still winter in the house despite being spring outside refers to the atmosphere of
reserve and distrust which has presumably being going on for over seven months, since Johns
affair with Abigail ended and Elizabeth sent her away. John blames Elizabeth for her coldness
and indeed, Abigail also says she is cold (contrasting her with John, to whom she says in Act I:
You are no wintry man.). Elizabeth herself says in Act IV:

It needs a cold wife to prompt lechery.

However,
it is quite possible that the affair has created an atmosphere of doubt and distrust between
them which is just as much Johns fault as Elizabeths, and which he has done little to dispel. In
any case, they both feel the coldness of the atmosphere and neither seems able to do much about
it, until larger events in Salem render their quarrel insignificant.