Yes, your limited company can start its own pension scheme at any time.
Normally company pension schemes are set up for any companies who have a specific number of employees. Being over a certain size requires companies to arrange a pension scheme, then take contributions from salary and complete regular contribution uploads to the provider.
Brookson Advice:
If you are a director of a limited company and do not have any employees, we recommend that you set up the Aegon SIPP in your own name then make employer contributions directly from your limited company. If you are IR 35 captured, then you should consider contributions via any employment ( PAYE or Umbrella you may have).