Hello, so my first pelargonium seeds sprouted (after just 4 days!) and so I removed them from the dome and mat and placed them by my windowsill. I raised the blinds so that they could get direct sun. I don't know how much sun is too much as I am in Arizona and it can get very hot.

So my questions are:

1) Is too much heat bad for them? I know my grown plants sometimes wilt when it's hot so worried with the seedlings being smaller. I am guessing right behind the window it may be as hot as 85-87 degrees.

2) At night it gets quite cold, like low 60s' would they benefit from the heat mat put at a very low setting? or maybe I should just move them away from the window sill? Unfortunately I do not have lights nor a fan.

3) the other seeds haven't sprouted yet, so they are still under the dome and heat mat. However, when I raised the blinds, to give sun to the sprouted ones, I noticed a couple of hours later that the thermostat told me the soil was 90 degrees! Eeek! I forgot to cover them with something to prevent the direct sun. Did I just kill them? The dome is now covered with some cardboard. Bad, bad plant owner!