Last year's cute Christmas present was one of those indoor hydroponic garden units. It now sits in a box in the storage room waiting for the spring garage sale. The spindly lettuce and greens leaves weren't worth eating.

I've never tried a winter veg garden except for what plants come up from summer seeds and they don't take off and really grow until the sun gets stronger in the spring.
They were left out without cover or mulch wherever they sprouted and grew gloriously in spring but not in winter.

I'm just concerned that your plastic might block too much of the weak summer sun and the plants get tall and spindly reaching for more light.
Hope it works out for you wherever you are.

I think reemay or spunbond fabric would work better- no chance of cooking your seedlings and it offers a decent amount of protection temp, predator and moisture wise. I've noticed that beds i seed for lettuce & other winter/spring crops consistently do much better with reemay than without, plus it protects from birds, deer and aphids, somewhat. Clear plastic could work, but you'll have to be sure it doesn't touch the leaves or they run the risk of cooking on a full sun day and it can overheat fast. No such danger with spunbond fabric- you can leave it right on the plants and they'll push it up as they grow. i've been using it that way for years. Oh, and it does last a long time, at least for me- i typically get several year's worth out of each piece- i'd guess at least about 8-10 season's worth. I usually use it spring, fall and winter, but you can use it in summer, though i bet it would degrade faster.

Dottie, i think an indoor hydroponic thing is vastly different than growing outside under even the weak winter sun and plastic. My cool greenhouse is attached to the house and only gets a few hours of direct sun in the morning, yet those plants are happy happy happy compared to the ones i bring in and even situate in the sunniest window inside. Even when it was done with double layers of plastic, before we had the 'real' greenhouse, the difference was amazing. Our best lights inside just don't compare to the sun.

mdfurever - most seeds require 70 degrees to sprout which is why I usually start the seeds in flats indoors under lights and then after they've grown a bit send them outside to grow bigger.

This year, even though I started seeds every two weeks, every head of lettuce is the same size and getting ready to bolt. The neighbors and co-workers are about to call me Lettuceman - we're all sick of salads.

December is a hard month for plants, there just isn't enough light during the day for much to happen. Days are short and the light intensity is low - not to mention how cold it can be.

If your seeds are in the ground, do not worry. If they don't sprout now they will sometime between now and May. The plants usually grow fast once things warm up (better than spring sown seeds).

I have been harvesting cauliflower, spinach, lettuce, collards, savoy cabbage leaves, mizuna and several other kinds of Asian greens, all of which were sown in September. (I can pick one leaf per plant from beets, spinach and lettuce several times a week and the plants last for months this way.) Broccoli plants were not planted until around the first of Oct and only now do they have golf ball sized heads. At night and some days all of these are covered with 0.5 ounce frost cloth that I get from Fifth Season in Raleigh (I am not sure if it is Remay or not). Their store in Carrboro stocks three sizes (0.5 ounce 7 or 10 feet wide and 2 ounce 7 feet wide) which they sell by the linear foot, so you could buy as little as you need rather than a complete roll.
On nights that the temp is expected to reach or go below freezing, I add a layer of plastic over the cloth over the cauliflower because the heads are easily damaged by freezing. Later in the winter I will also add plastic over the other beds whenever the temperature is projected to drop into the low 20's or teens.
All of my beds are raised and measure 4 feet by 8 feet. To support the cloth and /or plastic covers, I buy 9-gauge wire in 50 foot roles from Lowe's, cut it into 7-foot lengths and make about 4 hoops per bed to support the covers. Taller plants like cabbage, broccoli and cauliflower require longer hoops to keep the covers above these plants.
One other suggestion. I cover the paths between the beds with pine needles to keep the cloth covers from getting dirty.

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