CREATE TABLE table_30951 ("Home team" TEXT, "Home team score" TEXT, "Away team" TEXT, "Away team score" TEXT, "Ground" TEXT, "Date" TEXT)

When was the home team Essendon?
SELECT "Date" FROM table_30951 WHERE "Home team" = 'Essendon'
SELECT "Date" FROM "table_30951" WHERE "Home team" = 'Essendon'