so when to grow

 Hi guys, its been a while but now I am back, last year learnt lots of newbie lessons, sowed just about everything too early, poor weather and lack of sun caused most of my things to not fully mature, my best success spuds and zennia, so when do i sow peppers, tomotoes and pumkin this year, feb was too early, but i notice people sowing already, have sold my house and will soon have my greenhouse instead of one in my lounge 

Thanks MOS, the chart is really helpful