This is a great ground-cover with blue/purple/pink flowers in spring that the bees love. It is very effective at covering the ground and suppressing weeds.
There are a number of varieties. One of my favourites is 'Ajuga Black Scallop'. This one has dark mahogony/black glossy leaves and in spring, deep blue flowers. It grows to about 15cm high.
'Caitlans Giant'- Blue flowers and Purple red foliage. 30cm high.
'Chocolate Chips'- chocolate coloured leaves and light blue flowers. Leaves are longer and it grows to about 15cm.
'Jungle Beauty' - Green/brown leaves with nice blue flowers. 25cm high.