All up, not bad for starters.
I assume you're shooting in either Program or Full Auto mode,
which is fine for starters although aperture-priority,
shutter-priority or full manual mode will be a lot more fun once
you get accustomed to the camera.
It looks like all of the garden shots were taken on cloudy days
- if you'd shot in RAW you might have been able to give the photos
a bit more oomph by setting your white balance to "cloudy" or
playing around with temperature settings. You might still be
able to get a bit more out of it by playing with hue and saturation
in DPP.
The exposure in the last photo was set off by the bright
foreground - evaluative metering will do that. Try setting
your metering mode to spot metering before taking the shot so that
the flower doesn't come out so dark.
Thanks for the advises! Yeah, I think some of the shots were
taken using the auto mode. After a few days of playing around with
the camera, I am now using both the aperture and shutter priority
mode and it is indeed more fun!
P.S. I looked at some of your shots you posted in this forum and
they are great!
