Maltawildplants.com is now considered an online flora of the Maltese islands, portraying more than 900 species of plants found in Maltese habitats. It harbours a forum created in 2005 were memberes discuss topics about the Maltese flora and ID of plants.
The leaves were as large as my hand streched flat (c. 12-18cm). Beta vulgaris subsp. maritima usually have smaller leaves right?!? and I found no other Beta spp. in Haslam/Weber