How can I make a circuit to water my plant

I am put a circuit together on a PCB which will run a fish pump to suck water up and into my plant. I need the circuit to activate once a week so I need some sort of timer.
My original idea was to have a 555 timer running at its lowest frequency, connected to a series of flip flops so that every so many ticks the pump will receive its voltage and reset the flip flops. However, as far as I can see the 555 has a lowest f of 0.1Hz meaning 16 flip flops for a week of seconds.
Should I continue with this idea or has anyone got any better suggestions?

Thanks a lot!

Will

Your idea was the most effective and simple way to achieve your task. Go ahead !
The 16 F.F. can be replaced with 1 to 16 counter chip.
VCR has this timer circuit that can control On and Off time precision accuracy on Date,Hour and Minute within 7 days period. It runs with a special made IC.