In the garden: Dec. Plant a pineapple; start a compost

The Monitor's monthly garden calendar is based on length of growing seasons.

Note: Some items in each region can be applied to other regions -- such as information about potted plants and gift ideas. Region A (2 1/2-3 1/2 months

December is the month many gardeners get the jump on the growing season by writing for and studying seed catalogs. Try growing geraniums from seed in 1986. By ordering in December, you can sow in January or February so you will have fat bloomers by the time Memorial Day rolls around. The plants will cost a lot less than if you bought them potted in 4-inch pots. If you don't have a sunny window, you can rig up a standard fluorescent light fixture over a bench to start seeds and roo t cuttings. Light should be no more than 3 to 4 inches above plants. The Norfolk Island pines (Araucaria heterophylla) you see in florist shops and greenhouses can make good potted Christmas trees. Given the right care they will grow bigger each year. They do best at temperatures between 50 and 70 degrees F. and like a liquid feeding about every 3 months. Soil should not dry out but should never be soggy. Use tiny tree lights only, and make sure they don't touch foliage or stems. T rees will grow in a sunny window, or in one with filtered sun, and can be moved outdoors during summer. Keep holiday poinsettias watered daily; give bright light but avoid direct sun and hot radiators. Just one drying out will cause leaves to curl and drop. You can protect fruit trees from deer damage by hanging bars of highly scented soap in branches. Of all the repellents we've used, this seems to be most effective. It's good for all regions of the country. Region B (3 1/2-5 months)

Give a gardener a gift package of sterile soilless mix and some Jiffy 7 pellets. These popular pop-up pellets are ideal for novices because the ``pot'' and sterile medium are compressed in a pellet the size of a gingersnap. Just add water and the pellets swell to seven times their size (hence their trade name). They are handy for starting seeds or rooting cuttings. Be sure they don't dry out and keep them where it is 68 to 72 degrees F. (night and day) for good seed germination. Include in the

gift package a small horticultural heating cable to maintain proper temperature. In Regions A, B, and C, folks with sunny windows can make mini greenhouses to protect seedlings and houseplants from the cold by using a sheet of polyethylene or plexiglass on the inside of the window, leaving an inch of air space for insulation. Most houseplants, except tropical foliage plants and African violets (and their relatives), thrive if temperature is 55 to 60 degrees F. at night. However, below-zero nig ht temperatures, with high winds, can chill unprotected plants left near glass windowpanes. Draw shades and move plants away from window. Apples, pear trees, and grapevines can be pruned now and throughout the winter. If you didn't get latex paint on the trunks on the southwest side in fall, do it on a day when temperature gets up to 45 degrees F. This will prevent southwest injury (lengthwise cracking) when daytime temperature rises fast after a sub-zero night. Folks in Region A should be aler t to this possibility, also. Don't waste those kitchen scraps; start a garbage can composter. Punch 4 holes near the center of the bottom of a garbage can. Set on 2 cement blocks with saucer to catch moisture; add a little soil, shredded paper, or leaves to bottom (also after each day's garbage) and you'll have rich humus for your garden. There's no odor. If you want more details, send a SASE for ``Garbage Can Composting'' care of this paper. Region C (5-7months)

While outdoor chores are slack, try growing some out-of-the-ordinary plants indoors. Why not a pineapple? Select a fresh pineapple with lush green top (avoid straw-colored spikes). Remove the crown (top) by twisting if off. Trim off any flesh remaining. Strip off 3 or 4 leaves, then place the crown upside down in a dry, shady place for about a week. This lets cut end and leaf scars callous over. Set the top in a 6-inch pot of good, loose soil (one of the soilless mixes with some garden soil ad ded is fine). Water sparingly (keep soil ``just moist'') until roots form, then gradually increase water as needed. In Hawaii, it takes a crown 24 to 26 months to produce fruit. At about 18 months, slip a plastic over top and put an apple inside. The ethylene gas from the apple will induce the plant to bloom and form fruit. If humidity is low and air is dry in your home, don't be afraid to give your houseplants a shower bath weekly. Use tepid water and set the plants in an airy place to dry. Do

this in the morning so they have a chance to dry off before they are exposed to lower night temperatures. Take cuttings of holly bushes (either your own or a neighbor's -- with their permission) and root in moist perlite, vermiculite, or Jiffy-7 pellets. Be sure to select twigs from both male and female (berried) bushes. Region D (7-8 months)

Want some home-grown posies to give your Valentine? Start some dwarf zinnias in pots. If you have 5 to 6 hours of winter sun (or can stretch what you have with fluorescent lights), seeds planted in soilless mix (and germinated at 75 degrees) before mid-December, should be in a good bloom by mid-February. Plant 3 or 4 to a 6-inch pot. Some varieties to use are: Cupid, Button Box, Thumbelina, Pulchino, and Peter Pan. Seeds don't need light to germinate, so they could be moved to a warmer spot wh ile germinating and then grown on at 60 to 65 degrees F. Make sure eave troughs don't drip on evergreens. Ice can form on leaves, causing browned areas. Also, soggy areas around roots can smother the shrubs. Don't let leaves or other mulch material work its way close to trunks of fruit trees. This encourages nesting of mice and voles (not moles). A ``trombone sprayer'' is a dandy tool for home gardeners (make a gift of one to yourself or a family member). Just fill a p ail with the solution and drop the bottom end in, while pumping the other end like a trombone. They're ideal for giving a dormant oil spray to ornamentals and fruit trees. It's especially good for scale insects on magnolias, lilacs, junipers, etc. Make sure temperature will be 45 degrees F. or above for the next 24 hours when you apply the dormant spray. Sharpen your pruners and give your fruit and nut trees a ``going over.'' Hold off on peach trees until March. If you're afraid to prune grapes , remember, it's better to do some pruning than no pruning at all. No pruning produces lots of growth, few or tiny clusters of grape berries. Grapevines respond to heavy pruning and you won't hurt them if you happen to be overly enthusiastic. State agricultural colleges have bulletins with explicit directions for pruning. Pick up some paper white narcissus bulbs and grow in soil or just pebbles and water. They do not need to be precooled, so can be forced right away. Stagger planti ng so you can have a continuous show (and fragrance) for a month or so. Region E (8-9 months)

Treat yourself to a rain gauge so you can measure the amount of water falling on your garden. They're inexpensive and many models are available. Place the gauge in an open area, be sure it is plumb, and keep a regular record, emptying it out after each rainfall. In summer, it's a good idea to keep a rain gauge under your sprinkler so you can get some idea of how much water you're using. Ponderosa lemon lives up to its name. Grown in tubs, so it can be outdoors during summer and mo ved back in during cold weather, it can grow fruits the size of softballs. Black sooty mold on citrus (called sooty blotch) can be caused by aphids or scale insects that give off a sticky material that catches the sooty spores. Wash foliage with dishwashing detergent solution (1 tablespoon per gallon) or use insecticidal soap. If you don't have a coldframe or a hotbed, build one now. They're mighty handy for growing on your spring seedlings and transplants. Dig up the soil in your raised beds and other garden spots, after adding compost or rotted manure to be worked into the soil. Then you won't have to work it up in spring when you're short of time and also may have to cope with soggy soil. Christmas poinsettias give more mileage if kept in a cool room at night (50 to 60 degrees F.). During day, move to bright window and keep at 70 degrees F. Keep soil uniformly moist at all times. Modern varieties keep until July or August with little care. For perky home- grown gifts for Valentines, sow dwarf marigolds. Red Pygmy (Burpee seed company) and Red Cherry (Park Seed) will bloom in about 10 weeks if given a sunny window for 5 to 6 hours daily. Many florists and garden stores have ``treated'' hyacinth bulbs which can be forced in just plain water (in a special hyacinth glass). If instructions are followed, they bloom in 28 to 35 days. Christmas cactuses do best if they are grown in a cool room. Don't let them go dry while blooming or buds a nd blooms will drop off. Kalanchoes (Kal-an-ko-ees), popular holiday gift plants, will often bloom again if spent blossoms are cut off immediately and plant is moved to a cool room with plenty of light.

REGION F (9 to 12 months)

Some parts of region F have sandy soils and almost year-round growing conditions, interrupted only by late summer extreme heat. Others have one long season, terminated by two or three months of killing frost. Some gardeners have to contend with hardpan soil found in many areas of the arid Southwest. Practices that should be common to all areas are mulching and composting. Humus, the backbone of compost, loosens up a heavy soil and tightens up a sandy soil. Mulching prevents winter rains from l eaching nutrients from the soil. In frosty areas a ``green manure'' crop such as annual rye grass can be helpful if sowed now. Or you can apply manure, rotted straw, hay, or leaves and work them in after weather changes. In all high-heat areas, order heat-hardy varieties such as Contender green bean. It is considered best for Region F because of its uniformity, higher yield, and ability to bear longer in hot weather. Another bean that does well in Zone F is Florida Speckled pole lima bean, whic h some gardeners interplant with corn. This variety may be known by other names such as: Florida Butter, Old Florida Pole, and Speckled Beauty. If you're an heirloom bean buff, write for a catalog to Wanigan Associates, 262 Salem Street, Lynnfield, Mass. 01940. Or write to Vermont Bean Seed Company, Garden Lane, Bomoseen, Vt. 05732 for their catalog. They have seeds for all Regions. Faithful tomato varieties for Region F are Big Boy, Fantastic, Celebrity, Walters, and Homestead. These take the heat when others peter out. Citrus and other fruit trees should be inspected for broken or dead branches so these can be promptly removed (don't leave stubs). In areas where citrus can grow, vines can be planted outdoors; otherwise plant in pots and grow indoors during cold months, moving pots outdoors later on. Both a male and a female vine are needed to produce fruit, although some folks like them with their soft, fuzzy leaves as ornamentals only.