Turnips, rutabaga fall prey to maggots

Q: I enjoyed your column about turnips so much, my mouth was positively watering until I remembered my own experience with them – ugly maggots or worms or something which pretty much ruined the turnip. As an organic gardener, how can I combat these? – N.R., Presque Isle

A: Turnips and their cousin, the rutabaga, belong to the cabbage family. Quite possibly, your turnips have fallen prey to the extremely unpleasant cabbage root maggot. Damage may include stunted plants that wilt in the midday sun, roots that are mined, tunneled, and eventually, rot. Typically, tiny white maggots can be found in the damaged roots.

Organic remedies to this pest include preventative measures: Place a cardboard disk on the soil surface around the base of each transplant or seedling. Wrap the stems of the young plants with paper 1 to 2 inches above the soil line. This may help protect the plants from infestation. If plants do become infected, drenching the soil around the plants with parasitic nematodes may minimize crop damage.

Q: I harvested an abundant crop of carrots this year, but all the roots were misshapen. I think my soil is too rocky. Is there anything I can do to prevent this from happening to my carrots? – D.W., Machias

A: In short, there are two ways to avoid misshapen carrots: change cultivars or manipulate the soil.

Fortunately, plant-breeding programs have endowed us with a variety of tasty carrots that reflect a range of growth habits. Chantenay carrots are tapered and stout, Nantes carrots are long and evenly shaped, from top to bottom. Danvers carrots grow wide near the soil line and develop a blunt point at their tip and Imperator carrots are long, deep-rooted carrots that maintain a slender shape from the soil line downward.

Thankfully, a fifth group, the ball-type, are plump, adorable little carrots that barely dip several inches beneath the soil line. If your garden soil is rocky, you may be able to free the first few inches of soil from stones and sow ball-type carrots with success.

Alternatively, you may want to create a rock-free, raised bed in which to produce your sweet, tender roots. A raised bed may have sides (boards, stone, brick or any other appropriate material) or may simply be mounded soil that measures to a depth of 6-12 inches. The raised bed should measure between 3 and 5 feet in width, so that carrots may be harvested from either side of the bed.

For carrot production, create a raised bed with materials such as finely screened loam, compost, leaf litter, peat moss and sand. Too much nitrogen in the soil tends to produce soft carrots that may be misshapen or forked. They may taste poorly, as well, and have rough outer skins. Thus, in building a raised bed, avoid using material such as fresh manure that enrich the soil too much.

Q: How does one protect young fruit trees from winter damage caused by marauding mice?

A: In early autumn, rake away all fallen fruit, leaves and mulch from beneath the tree canopy. This should help prevent mice from forming nests under the trees.

In late fall, once rodents have made winter nests elsewhere, apply an 8- to 10-inch layer of mulch beneath the canopy of the tree, leaving a 10- to 12-inch ring around the trunk free of mulch.

This tactic may go a long way in preventing mice from girdling the tender bark of young trees in winter.

As snow falls, use your foot to tamp down the snow around the tree trunk. The compressed snow should prove too difficult a material for mice to penetrate.

Diana George Chapin is the NEWS garden columnist. Send horticulture questions to Gardening Questions, 512 North Ridge Road, Montville 04941, or e-mail them to dianagc@midcoast.com. Selected questions will be answered in future columns. Include name, address and telephone number.