Modern sprinkler timers have unlimited number of programs and they can run them simultaneously.

I am using RainMachine this summer and it works.

Here is a link that might be useful: RainMachine

troy,

I may be missing something and I would appreciate if it was explained to me. Residential controllers are usually 2-4 programs for different plant types(sprinklers vs drip, etc). Any program can be accessed at any time as long as times don't match. Different zones can not be run at the same time. So an example: ProgA zone1 can be 9:00 am for 5 minutes duration and ProgB zone 1 can be 9:15 am for 5 minutes which gives zone1 a rest to soak in between waterings. Both ProgA and ProgB can not water zone1 at 9:00am nor can ProgA zone1 and ProgB zone 2 run at 9:00am. Two zones running at the same time will lower the flow and pressure of both zones. That is the reason for having zones in the first place if the system isdesigned properly. JMHO Aloha

Check to see if you have enough water pressure and your transformer has enough current to drive at least 3 valves (if you have master valve).

I know BlueSpray can be configured to run programs either serially or concurrently.

Here is a link that might be useful: BlueSpray