This year I grew rutabaga for the first time. Since it is in the cabbage family, I put the rutabaga seeds in mid spring in the same bed under cover with other cabbage family members like broccoli and parsnip. I wanted to protect this bed from the cabbage worm. The type of cover that I used was the summer weight fabric from Gardeners Supply Company. According to Gardeners, it allows 85% of light to come through.
Here are helpful tips for growing rutabaga: 1) Sow the seeds outdoors about 1/4 inch deep under a single cover in the Spring. If you decide to plant earlier, then you should consider using two covers. Personally, I don’t like to go in the garden prior to the first day of spring or March 20th! The preferred soil temperature for germination is between 55 and 75 degrees Fahrenheit. 2) Since rutabagas can tolerate partial shade and can be attacked by cabbage worms and other bad bugs, I would suggest that you continue to use a lightweight fabric OR use a shade cloth and some sort of netting with small openings to keep those bad bugs away. As for partial shade, rutabagas like between 4 and 6 hours of sun. 3) Thin or space the seedlings about 6 inches apart. 4) Give the seeds and young seedlings some water via a watering can in the spring and provide water through soaker hoses once it is safe to turn on the outdoor spickets. I know you may not live in a cold climate but I do! 4) If you give the seedings any nutrients, I would suggest using a balanced plant food. If your soil needs more help, you can supplement with bone meal which is good for strong roots.