For the Earth you will be using White, Green and Blue, colour changes are in bold.
Rnd 1: With Green, working into a magic ring, 1 ch, 8 dc. 8 sts
Rnd 2: With Green, [2 dc in next st] seven times, change to Blue, 2 dc in next st. 16 sts
Rnd 3: With Blue, 1 dc, 2 dc in next st, change to Green, 1 dc, 2 dc in next st, 1 dc, change to Blue, 2 dc in next st, 1 dc, change to Green, 2 dc in next st, 1 dc, change to Blue, 2 dc in next st, 1 dc, 2 dc in next st, change to Green, 1 dc, 2 dc in next st, change to Blue, 1 dc, 2 dc in next st. 24 sts
Rnd 4: Change to Green, 2 dc, change to Blue, [2 dc in next st, 2 dc] twice, 2 dc in next st, 1 dc, change to Green, 1 dc, 2 dc in next st, change to Blue, 2 dc, 2 dc in next st, 2 dc, change to Green, [2 dc in next st, 2 dc] twice, 2 dc in next st. 32 sts
Rnd 5: With Green, 1 dc, change to Blue, 2 dc, 2 dc in next st, [3 dc, 2 dc in next st] four times, 3 dc, change to Green, 2 dc in next st, change to Blue, 1 dc, change to Green, 2 dc, 2 dc in next st, 3 dc, 2 dc in next st. 40 sts
Rnd 6: Change to Blue, 2 dc, [2 dc in next st, 4 dc] twice, 2 dc in next st, 2 dc, change to White, 2 dc, 2 dc in next st, change to Blue, [4 dc, 2 dc in next st] twice, 4 dc, change to Green, 2 dc in next st, 4 dc, 2 dc in next st, 2 dc. Ss into first stitch of the rnd. 48 sts
Cut the White and Green yarns leaving short tails, fasten off and sew in the ends. Cut the Blue yarn leaving a 30 cm / 12in tail, fasten off, sew onto the square and sew in the end to secure.