The state plans to issue grants to organizations seeking to buy and protect Hawaii lands that have environmental, cultural and agricultural importance. 

Sept. 16 is the deadline for applying for the grants. The state Department of Land and Natural Resources said Tuesday it would make applications available online at the end of the month. 

Legacy Land Conservation Program grants are supported by revenue from the state’s land conveyance tax. About $4.5 million may be available in grants for 2011-2012. 

Last year, the grants funded the purchase of agricultural lands in North Kohala and on Oahu’s North Shore. They also paid to buy the Hawea Heiau Complex and the Keawawa Wetland site in Hawaii Kai. 

The purchases were helped by $7.6 million in matching funds from federal, county, and private sources.