Coping with rain and wedding locations.

In uncertain weather, you can try to book indoor greenhouses.  Here is another Allan Gardens wedding, when we were fortunate to have (almost) the entire place to ourselves.  Try for off-hours bookings, midweek or early or nearer closing. And expect crowds, who are not complying with the contract they signed with the City.
Pity, really.

The view of the Rose Garden from the St James Pavilion is lovely right now, tho.