Your home insurance limit is not necessarily the value of your property. It is only used to cover the improvements on the land that you have made.
The theory is that land does not get damaged by a fire or wind or other disasters that ruin your house. The value of the land will still be the same even if your house burns down.
If you happen to have very expensive landscaping done, such as special trees, you should consult with your agent and see if you can specifically list these on your policy.