Free Growing Your Own Vegetables: An Encyclopedia of Country Living Guide by Carla Emery, Lorene Edwards Forkner Page A

mulched and left in the garden in areas with mild winters.
    Parsnips
    Parsnips ( Pastinaca sativa ), a pale relative of the carrot, are just about the hardest-to-grow root vegetable, but worth the trouble because of their winter-keeping ability; parsnips can handle and even thrive on being left in the garden all winter, to be dug up as needed. Their long tapered roots are covered with a smooth, light-colored skin, and their flesh cooks up soft and sweet.
PLANTING: The key to parsnip success lies in a well-prepared, rich soil; fresh seed (parsnip seed doesn’t keep well for more than a year); and a cool climate. Provide a deeply dug, well-drained, sandy soil to promote long straight roots. Unlike carrots, parsnips benefit from ample quantities of manure and fertilizer. Because they are even slower to germinate than carrots, it is recommended that you similarly sow radish seeds along with the parsnip seeds to mark the planting. Wait until the soil has warmed in spring to plant, as parsnips will be even slower to emerge in a cold soil. Sow the fine seed very shallowly, ½ inch apart, and cover with ¼ inch of soil; keep the soil well watered, as parsnips will not come up through a dry soil crust. Space rows 18 to 36 inches apart depending on your available space and soil fertility. Keep plantings free of weeds throughout the growing season. 110 to 120 days to maturity.
 
HARVESTING: We’re accustomed to rushing sweet corn from garden to cooking pot because its abundant natural sugar starts changing to starch the minute it leaves the stalk. Parsnips reverse that process: they contain lots of starch that, when the plant freezes, changes to sugar! Parsnips will get sweeter and sweeter if left in the garden over the course of a frosty winter. Begin harvesting in October by digging, not pulling, the long skinny roots from the soil. In particularly cold areas, a protective mulch will allow you to dig parsnips even when the surrounding soil is frozen.
    Radishes
    Radishes ( Raphanus sativus ) are the vegetable that spring-starved gardeners, anxious to get their hands in the dirt, always plant. Easy to grow and fast—you might have the first ones to eat as soon as 3 weeks after planting. The most familiar radish grown in the United States is cherry-sized, with rosy skin and peppery-hot, white flesh. Larger white radishes are generally milder than red varieties, take longer to mature, and are planted in late summer for a cool-season harvest—thus they are sometimes referred to as “winter” radishes.
PLANTING: Prepare a moisture-retentive seedbed that is not too rich. Red radishes do not require a deep soil; 6 inches is plenty, with seed sown ½ inch deep. Determine planting density by expected radish size, and thin seedlings to an eventual 2 inches apart in every direction. Because red radishes are quick to mature and do not tolerate summer heat, sow successively every 2 to 4 weeks, beginning in early spring. Plant later crops in the shade, water well, and mulch to keep cool.

Winter radishes must be planted to mature in cool weather for proper root development. Sow seed 8 weeks before the average date of your first fall frost, about 3 to 4 inches apart, and thin to accommodate spacing without crowding. If the season is dry, provide moisture to avoid tough, woody roots. 28 to 60 days to maturity depending on variety.
 
HARVESTING: Red radishes are one of the quickest-growing vegetables but do not hold in the garden once they are mature. Tender and crisp in their prime, within a few days they quickly turn pithy and soft. Thin and harvest the largest roots first, leaving the others to size up.
    Red radishes will store in the vegetable drawer of the fridge for up to a month.
    Winter radishes will hold for up to 3 weeks in the garden once mature, after which time they begin to toughen. Thinnings may be used fresh like red radishes.
ASIAN RADISHES
Daikon radishes are white and substantial—2 to 4 inches across by 6 to 20 inches