The National Weather Service has issued a frost advisory for tonight, Sunday, September 23. The combination of clear skies and cold air mass could allow temperatures to fall into the low 30’s with some areas of frost possible after midnight.

This might be the motivation needed to bring in tender potted plants or sensitive house plants that have been summering outdoors. I’ll be bringing in a scented geranium and a rosemary plant which have graced our front porch this summer.

I harvested a lot of tomatoes this afternoon, both fully red or starting to turn. The not-yet-ripe tomatoes are washed and dried, and then introduced to the Magic Tomato Bag. This process will only work with tomatoes who haven’t been touched by frost, so it’s important to act now.

It’s also a good idea to cover any tender vegetable plants whose lives you are hoping to extend. Tomatoes and peppers may survive if frost is kept off of the plants. We use sheets or light-weight plastic to keep the frost from settling on the plants. Again, the idea is to keep the frost from touching the plants so using a fence, trellis or support to keep the cover lifted is a great idea. Remove the covers in the morning so that plants can enjoy the sun.

Hardy plants such as kale, broccoli, and collards as well as fall mums should be just fine. Some folks hold that the flavor of kale and collards is actually improved by frost.

None of these methods are guaranteed. We like to give them a try because there still may be enough warm days ahead to make the effort worthwhile.

Michigan gardening writer, designer, and all-around advocate Janet Macunovich spoke at the most recent meeting of the Washtenaw County Master Gardener Alumni Association. I’ve attended several of her presentations, and I’m always impressed with her knowledge, energy and friendliness; even with 30 number of years in the field, she shares gardening information with an attitude of learning together, that is welcoming and not overwhelming. Her timely topic was “Art of Fall Garden Clean-up: Garden clean-up with an eye for winter beauty”. Macunovich emphasized perennial gardens, but many of the same principles apply to a garden with vegetables, herbs or annuals. I left the meeting inspired and ready to begin the fall clean task, which as Macunovich pointed out is a process, not a marathon.

One major point of her presentation was that gardeners should begin winterizing the garden as the leaves begin to fall– in other words, right now. Beginning the first steps of preparation are easiest when the garden is firm and organized as in fall, and not soggy and messy in the spring. Cutting and clearing plants in the fall also reduces the number of seeds left on the beds and therefore will lead to fewer weeds in the spring. She estimated that every hour spent cleaning up in the fall saves two hours of the same in the spring, and I can see how that number is totally right on. In the spring, weeds have the advantage; they put energy into growing as soon as possible, not when the weather is good enough for us to go out and work. Overall, fall clean up is much less stressful.

The first step is cutting plants down. How do you decide where to begin? Macunovich suggests that you take out what doesn’t look good to you personally. One point she underscored was the need to know your plants’ growth habits; sometimes it’s just a matter of becoming a more active observer in the garden. Does the plant regrow from the old growth or the crown? Since lavender, thyme, and evergreens grow off of old growth, don’t cut them down. If they need tidying up, give them a “hair cut” or trim instead.

Gardeners can leave sturdy plants like ornamental grasses or stonecrop sedum as points of interest in the garden. The choice is up to the individual gardener, based on what she or he likes. Some plants will attract birds, so blackberry lily or globe thistle can be left for that purpose.

Before clean-up begins, tools should be cleaned and sharpened. It’s also important to clean tools as you work, especially if you suspect issues with diseases. Paying attention to the plants’ health as you work will help you notice problems like pests or weeds too.

Macunovich sets a goal of being done with fall clean-up before the heaviest leaf fall. That way, leaves are on top of the garden as mulch and insulation, and they do not have to be cleared out of the way to get to the clean up. Like us, she’s a big proponent of covering the garden beds with a thick blanket of leaves before winter. Those leaves will break down over winter and add more organic matter to the soil.

Cleaning a whole garden as once can be a huge task, but beginning by spending 20 minutes at a time can make the chore much simpler. Taking the garden down in stages allows us to continue to enjoy the still lovely parts as we prepare for winter.

For more gardening information and advice, see GardenAtoZ, a really nice website put together by Janet Macunovich and Steve Nikkila. There, you can see wonderful pictures, subscribe to their newsletter, and benefit from their extensive gardening experience.

One way of categorizing home-grown tomatoes is dividing them into tomatoes for cooking and making sauce and tomatoes for slicing and eating fresh. Are the categories really that different? I think the answer is both yes and no.

For slicing and eating fresh, many people recommend Brandywine, Mortgage Lifter, Cherokee Purple, Black Krim, or Beefsteak tomatoes. These are among our favorites for BLTs, simple tomato salads, or slicing and eating with a bit of salt and herbs.

For the most part, slicing tomatoes are roundish in shape and large, although sizes may vary. These tomatoes are generally quite juicy.

When we make sauce, we like to use Amish paste, San Marzano or Roma tomatoes. Sauce or paste tomatoes tend to be more oval, or oblong, or pear-shaped. They are also considered to be “dryer” having less liquid and more pulp than slicing tomatoes.

Although I tend to use tomatoes along these categories, I’m not hard-edged about it. Some cooks swear by a certain tomato for a particular use, but I like to mix varieties for a more complex taste, whether in making tomato sauce– or apple sauce or pie, for that matter.

Overall, I would argue that home-grown tomatoes are pretty interchangeable (grocery store tomatoes, for the most part, are only worth eating in desperation in January no matter how they are prepared.) Sauce tomatoes will do for a salad or BLT in my book, and big juicy slicing tomatoes also make good sauce, although they will take significantly longer to cook down.

When preparing sauce using tomatoes that have a lot of juice or seeds, you can speed up the cooking process by seeding the tomatoes before cooking. The easiest way I’ve found to do this is the cut the tomato in half along on the equator, as it were, and then gently squeeze with one hand while gently prodding the tomato cavities with a finger. I don’t obsess over seed removal because I run tomato sauce through the food mill after cooking to make a smooth sauce.

The tomatoes are still ripening in our garden, so I’m looking forward to more meals of fresh and cooked homegrown tomatoes. We planted some new-to-us varieties this year, and I was a little uncertain about which was which. The fun and informative Ann Arbor Farmers’ Market blog contained a link to a guide to tomato varieties on Rutgers New Jersey Agricultural Experiment Station, so I have been able to identify the varieties we planted that I’ve been unsure about.

Our home-made tomato sauce has the potential of including about a dozen varieties of tomatoes. I’m not a purist, however, I know our tomato sauce will be red, delicious– and plentiful, I hope.

How selective are you about the ways you use slicing or sauce tomatoes?