Developing a grant proposal is a process. It takes time and careful thought to craft a winning proposal. The more time you give yourself, the greater your chance for success.
It can be helpful, therefore, to have an understanding of the yearly technology grant cycle. In general, federal grants have deadlines in the second fiscal quarter each year. Private foundations usually meet quarterly, while some meet twice a year.
There are exceptions to these generalities. It is important to know exactly when a grant is due in order to allow plenty of time for development.