Solar thermal makes use of the heat from the sun by directly heating water, either in a panel or in vacuum tubes.
Solar thermal works best in the hotter months
From spring to autumn (in the months when you do not need the heating on) your solar thermal panels should be able to provide a significant proportion of your hot water needs.
A wood boiler stove makes most sense used in the colder months
When you need the heating on your wood boiler stove can provide hot water and heating. This is at a time of year when your solar thermal will be contributing far less to your hot water needs. In the warmer months you do not need to light the stove as you will only need hot water.