At the end of the movie, Andy explains to Sydney that the reason he finally managed to give her a dozen roses and be President is "as it turns out, I've got a rose garden". The thing is: those fresh flowers couldn't have come from the Presidential rose garden. Said garden is outdoors, and the State of the Union speech which he was then walking to the congressional chamber for the purpose of delivering is delivered in the very winter month of January.
Presumably there's also a greenhouse where the White House gardeners can cultivate rosebushes in the off season for later planting.
Fridge Brilliance
Rumson is generating a lot of Moral Guardian negative press for the President but doesn't ever point out, "This is a conflict of interests for a lobbyist and the President to be involved." This is because it would easily resolve things with either them putting their relationship on hold or her quitting her job with the environmental firm. He doesn't want the conflict to end as that would make it a non-issue.
Of course, it's also surprising that nobody else raised this issue. Rumson can have his talking points all he wants, but trying to keep his caucus to that line (or even avoiding friendly fire from some off-script Congressman in the President's own party) seems less likely. Eventually some commentator would have raised the point. Moreover, the issue wouldn't entirely go away - "The President had to be called out on a blatant conflict of interest in a relationship he was having to realize the issue" is a valid line of attack that would have stuck around, and other elements of the relationship could have stuck around as well.
