Some Problems

There is no sound, graphics are not very great, I'm afraid, after a while there are always the same units (the flying ones came only once), the waves do not start without clicking on that coloured bar, and after level 37 or so it just stopped. No "game over", no high score, nothing.

Good for first game

You should tell the player which items are bad items. The flowers look too similar to see at first glance that some are bad ...
And maybe don't use a photo as background.