I know I haven't posted any photos from my garden since early August. This is because I was transitioning my garden from summer plantings to fall ones. Transition complete.
No, this is not the final resting place of Summer. I posted a similar photo on Facebook a few years ago and my friends commented that the covered garden beds looked like burial shrouds.
Row cover fabric lets rain water and sunlight through while keeping pests out. Different weights or thicknesses of fabric provide different levels of frost protection for winter gardening. I use row cover because it's the most effective organic defense against cabbage worms. These voracious pests consume crops from the Brassica family including cabbage, kale, collards, broccoli, cauliflower, Brussels sprouts, and mustard greens as well as the leafy tops of radishes, turnips, and rutabagas. Y'know, pretty much everything that I'm growing in the garden right now. If you leave your garden uncovered and you see a white butterfly that stops for a moment at your greens before flying away, check the undersides of the leaves for singly-laid tiny eggs (you might need a magnifying glass) and rub them off. Also be on the lookout for checkered whites for the same reason. Once the eggs have hatched, you probably won't see the caterpillars until they have already started to chew on leaves and excrete frass. Both species have globally secure populations and abundant food sources in the wild, so don't feel the slightest twinge of guilt from depriving them in your garden.
I've talked enough about row cover and why I use it, so let's take a peak underneath.
The four beds have been planted in much the same way. There's a central row of larger Brassicas: two beds have purple sprouting broccoli and two beds have 'Rubine' Brussels sprouts (it's Brussels in this photo), all interplanted with leeks. In parallel rows on either sides of the larger Brassicas are root vegetables, a different type in each of the four beds: rutabagas, 'Watermelon' radishes, beets, and turnips. This bed happens to be planted with radishes. In all of the beds, a mixture of leaf lettuces are planted along the longer sides and arugula is planted along the shorter sides, which will provide fresh salads all fall and into the winter. I've already started nibbling on the arugula, adding a handful to sandwiches. There are also some welcome volunteers scattered throughout: cilantro and dill.
I placed a little bit of straw around the central Brassicas and leeks because I planted them as seedlings. The rest are from seeds sown directly into the beds. Once I am satisfied that the seeds have sprouted, I will mulch the entire surface of the soil with straw. The straw mulch will help to insulate the plants against the coming cold weather as well as slow the rate of evaporation of water from the soil's surface. As the straw decomposes, it will further nourish the soil.
There you have it, row cover and mulch, the "secrets" to cool season gardening in DC.