1.Rutabaga and turnip are family. As a general statement, Rutabaga is much larger and has a much longer DTM. In most cases that means you will need larger spacing both between plants and between rows.
2. Rutabaga turnip has two meanings that I know. (a) many vendors will include a statement with Gilfeather turnip seeds that it has Rutabaga characteristics. In size and DTM it is roughly half way between a standard turnip and a rutabaga. You will sometimes see a statement that it is sweeter than a turnip. However turnips come in many sizes, shapes and colors. Many are much sweeter than the Purple Top White Globe they are using for comparison. I would expect a vendor to know variety names. (b) I heard a few older southerners use the term rutabaga turnip for standard rutabaga.
3. Rutabagas like all brassica One seed one plant. as far as spacing, minimum for most rutabagas is 8 inches. They do not bulb up well when crowded. You can get away with 6-8 spacing with a Gilfeather.
Rutabaga (Brassica napus 'American Purple Top') Rutabaga (Brassica napus 'Helenor')
