"Rogation" is derived from the Latin verb rogare, to ask. Farmers have finished sowing. The seeds of corn, the seed potatoes and all the other crops are now in the ground, waiting for rain and warm sun to make them grow.
For hundreds of years, on Rogation Sunday, Christians have asked God's blessing on their crops - and prayed for a good harvest later in the year.
Even today in some country villages, instead of meeting in church, the people walk out together to ask God's blessing on each field. In olden times, they stopped under an oak tree and there the priest would read from the Bible. Such trees were known as Gospel Oaks. (There's still a station in north London called Gospel Oak.) Also at this time of year (often on the Thursday following Rogation Sunday), people went out "beating the bounds". The village children would be marched around its boundaries, stopping at each landmark - such as a large tree or stone. At these points, one of the boys would be beaten with willow sticks. If the boundary was a river, the boy would be ducked in the water.
One thing was certain, once you had taken part in "beating the bounds", you remembered where the edge of your village was - and you didn't go beyond that boundary. And the victim usually didn't mind too much as he would have been rewarded with a silver shilling.
In Scotland, the custom is known as "riding the marches" or "common riding". An account of one such observance can be found at www.cyberscotia.comancient-lothianindex
A prayer (or "collect") and readings for Rogation will be found in the traditional Church of England Book of Common Prayer under the heading "Fifth Sunday after Easter".
Using Google to search "Rogation" will locate a number of parish sites describing local customs. Try: www.elca.orgdcmworshipfaqoccasional_servicesrogation_days and http:intervarsity.uchicago.edukalrogation