There are good reasons to plant turnips even if they aren't on your list of vavorite vegies.
Turnips will almost never be the answer to the question of “What is your favorite vegetable?” so maybe the title of this article should be “Cover Crop Plantin’ Time in the Mid South” but it just doesn’t have the same alliteration thing going on. BTW, it’s the last week of August, and a few harbingers of fall are already apparent – goldenrod in bloom for example.
Anyway, your summer garden is looking disgraceful (you know it is) and it’s high time to put all of those disease and weed ridden plants out of their misery before you get a visit from the homeowners association. Hopefully you are planning to grow a fall garden, but even so some amount of ground is probably going to be vacant once you tidy up – which is where cover crops come in. Any good cover crop will suppress weeds, prevent erosion, improve the fertility / organic content of your soil, and in some cases even put food on your table. One of the main things that cover crops do is to absorb soil nutrients into their tissues as they grow so that they don’t leach away during the rainy winter. But (to me) the main reason to plant cover crops is that they save work, because all of those advantages are gained with no more effort than it takes to sprinkle a few seeds on the newly bared ground.
The most popular fall / winter cover crops in my area are: Turnips, Crimson Clover, and Annual Rye. They are area favs for good reasons, and they all have their unique advantages. Rye probably does the best job of suppressing weeds, and adds lots of organic matter to the soil when you work it in early next spring. Crimson clover adds nitrogen in addition to organic matter. Turnips main claim to fame is the fact that they also yield food – all winter long in some cases. Ask around (at a farmers co-op for example) to find out what works best in your area.
Whichever cover crop you choose to sow buy your seed by the pound (at a farmers co-op or or Real Garden Center) unless your garden is awfully small a little paper packet isn’t going to be enough seed. Anyway, a pound of turnip seed should only cost 3 dollars or so, will last just about forever in the freezer, and contains enough seed to plant the entire state of Rhode Island – it’s one of those things that you should just keep on hand. If you keep them in an empty shaker bottle such as spices comes in it will be very convenient to just sprinkle about – a good tip for all kinds of salad green seeds.
The other thing you should do with any of these crops is to completely ignore the planting dirrections. One of those little packets will tell you that you need to plant turnips 1/2″ deep in loose fertile soil which has been enriched with lots of organic mater – which is true if you are hoping to win a ribbon at the fair, but for the purpose of a cover crop just sow your seed thickly (thin later with a hoe if you want to harvest roots) on top of the ground after you have pulled the old plants and weeds. You do need to use a rake or cultivating fork to break up any crust that you might have, and you will probably want to rake it out just to be neat – but that’s all. The main thing is to throw those seeds down and everything else will take care of itself. If you water one time after sowing the seeds you will probably see sprouts in 3-4 days.
But, you say “I’m planning on mulching/tilling/fertilizing/planting something else long before those cover crops will be done.” Don’t worry about it – when the weather cools off and you get ready to do any of those things just do it – until then your cover crop will be improving your garden for you, and if you don’t get around to those things until next year it will look like you planned it that way.
This is one of the best times of the year to work in your garden – get out there!