  We present ATCA results of a 3 and 7 mm continuum survey of 20 T Tauri stars
in the Chamaeleon and Lupus star forming regions. This survey aims to identify
protoplanetary discs with signs of grain growth. We detected 90% of the sources
at 3 and 7 mm, and determined the spectral slopes, dust opacity indices and
dust disc masses. We also present temporal monitoring results of a small
sub-set of sources at 7, 15 mm and 3+6 cm to investigate grain growth to cm
sizes and constrain emission mechanisms in these sources. Additionally, we
investigated the potential correlation between grain growth signatures in the
infrared (10 \mu m silicate feature) and millimetre (1-3 mm spectral slope,
{\alpha}). Eleven sources at 3 and 7 mm have dominant thermal dust emission up
to 7 mm, with 7 of these having a 1-3 mm dust opacity index less than unity,
suggesting grain growth up to at least mm sizes. The Chamaeleon sources
observed at 15 mm and beyond show the presence of excess emission from an
ionised wind and/or chromo- spheric emission. Long-timescale monitoring at 7 mm
indicated that cm-sized pebbles are present in at least four sources.
Short-timescale monitoring at 15 mm suggests the excess emission is from
thermal free-free emission. Finally, a weak correlation was found between the
strength of the 10 \mum feature and {\alpha}, suggesting simultaneous dust
evolution of the inner and outer parts of the disc. This survey shows that
grain growth up to cm-sized pebbles and the presence of excess emission at 15
mm and beyond are common in these systems, and that temporal monitoring is
required to disentangle these emission mechanisms.
