Early spring is probably THE MOST important time to prepare for the cycling season.
By getting in base miles now you will be able to enjoy months of cycling. As much as I hate many of these early rides, I know that the benefits are worth the effort. Try to get out as frequently as possible during the week, even if it is only for 45 minutes before the sun goes down. On the weekends try to get in longer rides of at least a couple hours duration. If you have a heart rate monitor, stay in zone 2 for the duration of the ride.