From Webkinz Insider Wiki
Buying a Yard
There is only one size of Outside Yard. It is the same size as a Large Room, 10x10.
There are many items in Webkinz World that can only be placed outside.
For help figuring out what goes where, please visit Where Things Go in Webkinz World.
Keep in mind that fences can only go on the two far outside edges of the yard.
In Outside Yards, players can plant seeds and grow plants.
For more information on this, please see Gardening.
Graphics and Animation
Sometimes it "rains" in Outside Yards. This is an animated graphic that runs on the screen.
Keep an eye out for floating clouds around Mount Kinz in the far distance.
The appearance of ground changes with the season. There's snow in the winter, small flowers in the spring, bright green grass in the summer, and colored leaves in the fall.
The background graphics also change with the season, to match the ground graphics.