Humans have been unique in that we specifically plant seeds for plants that we wish to reproduce. We wait for them to grow to maturity, then harvest the products and plant again.
How common are such specific agricultural practices in Nature?
We can ignore seed cycles that pass through excrement which isn't an intentional process.
I can think of bees as specifically harvesting only the sugars from flowers. Selecting the flowers that they like. Pollinating the flowers in the process, and storing the sugars for a "rainy day". In a sense a very complex task for such a small bug.
Squirrels seem to have a propensity to plant seeds, but that may be more of an accident than any deliberate process.