- Set up a Google Calendar.
- Create two calendars; one for sowing (green) and one for harvesting (brown).
- Enter the information from all your seed packets into the relevant calendar.
By checking the weekly calendar you can see at a glance what needs to be sown and what could be ready to harvest.

I’ve set mine up to include a calendar for flowers too (orange) and also one that records the details of my allotment (pink), e.g. “Sowed sweet pepper, snowball cauliflower and nicotiana white trumpets.”