Saw this in a couple of branches. Each purchase I received a leaflet each with:
£5 when you spend £35 food/drink/flowers plants (x3)
£10 when you spend £50 food/drink/flowers plants (x1)
Plus one voucher for a free coffee when you make any purchase from their cafe (valid before 12 am 4th-13 April)
Different dates for the various vouchers.