Cool Plantings

The kids are back in school, the traders are back on Wall Street, and your garden looks like a kitchen the morning after a dinner party. Instead of putting that trowel away until next spring, enjoy what's left of the pleasant weather by working in the dirt.

EDIBLES: Fall is perfect for a second season of cool-growing vegatables and herbs such as lettuce, spinach, beets, cabbage, broccoli raab, kale, parsley, and cilantro. With proper mulching, some things will last in the soil right through the winter.

CONTAINERS: Step outside the traditional stock of pumpkins and corn stalk decorations with fall-themed containers. 'Lemon,' 'Peach,' and 'Orange' Symphony osteospermums are a nice substitute for the age-old chrysanthemum. Pansies now come in orange, bronze, brown, maroon, purple, and so-called black that make them great for Halloween and Thanksgiving decorating. Perennial foliage plants, too, look great in containers mixed with grasses. Try heucheras like H. 'Purple Petticoats' and the silvery green-purple H. 'Green Spice.'

TREES AND SHRUBS: You have plenty of time to plant before the ground is frozen. The cooler weather helps trees and shrubs get established without the added stresses of heat and humidity.

There's a considerable amount of moss that seems to be growing in my perennial garden, particularly in one section that is in shade to partial shade for most of the day. Is moss bad for the garden? Does its prevalence signify damp conditions? What can I do about it?
BARBARA A. PITONIAK
Northampton

Moss does indicate moist, shady conditions, but it's not a detriment to your garden unless it's growing where you'd rather have perennials. Remove the shallow-rooted moss by skimming it off the soil with a spade. Plant perennials in its place, or cover the area with mulch to inhibit the moss from reestablishing itself. Or leave it be. Moss gardening has been practiced in Japan for centuries. Moss can lend the garden a woodland feel when growing on and around rocks, fallen logs, and ferns. It's also an excellent replacement for lawns in moist and shady spots. Learn more about moss at mossacres.com.

I have a very shady backyard where I have a border garden against a stockade fence. I'd like to add some color to the garden, but everything I plant seems to die from lack of sun. I have tried impatiens and astilbe, but nothing survives.
BETTY IACONO
Lynnfield

Impatiens are usually dependable shade plants. Till some compost into your soil this fall to make sure it is providing enough aeration and water-holding capacity for the plants. Next year, try adding color with foliage plants that can add lime green, pink, yellow, burgundy, and white to the garden. Annual foliage plants include the hundreds of coleus varieties with fascinating foliage patterns, or the 'Charmed' series of Oxalis, which also produce lots of tiny white flowers. You can find heucheras in a range of colors. H. 'Dolce Key Lime Pie,' H. 'Dolce Peach Melba,' and H. 'Amber Waves' are some suggestions. Hostas are dependable shade perennials. Choose varieties with white, ivory, yellow, or lime-green variegations to brighten your shade. Bonus color will come from their white to purple flowers. The striated leaves of the Japanese forest grass Hakonechloa macra can also add color and movement to dark spots.

I have a large grassy (i.e., boring) yard, which I am trying to enhance with flowers and shrubs. I can't afford to drop a lot of money at one time, so last year I just added foundation shrubs across the whole property. It still looks rather bare, and I'm not sure what my next step should be. Should I keep slowly adding to the whole property, or just finish patches at a time? I find I'm rather impatient about the whole thing.
M.S.
Woburn

Installing all of the shrubs is a great start and gives you the bones for your landscape plan. To save money, plant one section of the garden with perennials you want to use in other sections. As they grow, you can divide and distribute them to other areas. Meanwhile, fill in bare spots with fast-growing and mounding annuals like petunias. That will buy you time until the shrubs mature and gain some character, and it gives you the flexibility to change your mind about plantings.

When I was living in the New York area, we had several mimosa trees in our yard. They're messy but gorgeous, and they smell great. I would love to plant a couple here, but wonder if they would survive in this climate.
SUSAN WOLFTHAL
East Bridgewater

Although it flowers best in areas with long, hot summers, Albizia julibrissin, also known as a mimosa or silk tree, is hardy in USDA Zones 6-9 and does survive as far north as the Greater Boston area. It reaches a height of 20 to 35 feet with an equal spread. The quick-growing mimosa is considered a weedy species in the South and is on the invasive plant list for several Southern states. According to Richard Claudio of Mahoney's Garden Center in Falmouth, a few Southern nurseries produce this "weed" in tree form, and provide Northern nurseries with 5-gallon specimens. Plant mimosas in a sheltered location, such as near a building, and

mulch with leaves, compost, or cow manure in winter. Also keep in mind that the delicate branches may break under heavy snow.

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