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Vegetable Garden


  MG Manual Reference
Ch. 10, pp. 55 - 62
[Gardening in the Fall: fall | season ]

Planting for a fall harvestTop
By planning and planting a fall/winter vegetable garden it is possible to have fresh vegetables up to and even past the first frosts. At the time when retail vegetable prices are on the rise, you can be reaping large and varied harvests from your still-productive garden site.
Many varieties of vegetables can be planted in midsummer to late summer for fall/winter harvests. Succession plantings of warm season crops, such as corn and beans, can be harvested until the first killing frost. Cool season crops, such as kale, turnips, mustard, broccoli, cabbage, etc., grow well during the cool fall/winter days and withstand light frosts. Timely planting is the key to a successful fall garden.
To determine the time to plant a particular vegetable for the latest harvest in your area, you need to know the average date of the first killing frost and the number of days to maturity for the variety grown. Choose earliest maturing varieties for late plantings. The formula below for determining the number of days to count back from the first frost will help determine when to start your fall garden.
Number of days from seeding or transplanting outdoors to harvest
+ Number of days from seed to transplant if you grow your own
+ Average harvest period
+ Fall Factor (about 2 weeks)
+ Frost Tender Factor (if applicable)
= Days to count back from first frost date
The Frost Tender Factor is added only for those crops that are sensitive to frost (corn, beans, cucumbers, tomatoes, squash), as these must mature 2 weeks before frost in order to produce a reasonable harvest. The Fall Factor takes into account the slower growth that results from cooler weather and shorter days in the fall, and amounts to about 2 weeks. This time can be reduced from 2 to 5 days by presprouting seeds. Almost any crop that isn't grown for transplants can benefit from presprouting. Sprout seeds indoors, allowing them to reach a length of up to an inch. Sprouted seeds may be planted deeper than normal to help prevent drying out, and they should be watered well until they break the soil surface. Care should be taken not to break off the sprouts when planting them.
When planting fall crops, prepare the soil by restoring nutrients removed by spring and summer crops. A light layer of compost or aged manure, or a small application of complete chemical fertilizer will boost soil nutrients in preparation for another crop.
Dry soil may make working the soil difficult and inhibit seed germination during the midsummer period. Plant fall vegetables when the soil is moist after a rain, or water the area thoroughly the day before planting. Seeds may be planted in a shallow trench to conserve moisture. Cover the seeds about twice as deeply as you do in the spring. An old-time trick for germinating seeds in midsummer is to plant the seeds, water them in well, and then place a board over the row until the sprouts just reach the soil surface; at that time remove the board. Plastic will also work, but must be completely anchored so the soil does not dry out underneath or the plastic blow away. Plastic, especially black plastic, may cause the soil to get too hot. An organic mulch on top will help keep soil cool. Mulching between rows can also help keep soil cool and decrease soil drying. In severe hot weather a light, open type of mulch, such as loose straw or pine boughs, may be placed over the seeded row. This must be removed as soon as seedlings are up so that they receive full sun. Starting transplants in a shaded coldframe or in a cool indoor area is another possibility.
Once young plants are established, a heavier mulch may be used to hold moisture and control weeds. Irrigate when necessary so the young plants have sufficient moisture. Fall plantings often have few insect problems, as they avoid the peak insect activity period of midsummer. However, some insects, such as cabbageworm and corn earworm, may be even worse late in the year than in summer; vigilance is still required! Avoid some pests and diseases by planting crops of different families than were originally in that section of the garden.
Some of the best quality vegetables are produced during the warm days and cool nights of the fall season. These environmental conditions add sugar to sweet corn and crispness to carrots. Parsnips and Jerusalem artichokes are examples of crops that are very much improved by a touch of frost.
Protection of vegetable plants during cold periods may extend your season even further. Though in the hot days of summer the last thing you want to think about is planting more crops to take care of, look ahead to the fall garden, which offers its own satisfaction through prolonged harvest of fresh vegetables, savings in food costs, and the knowledge that you're making full use of your gardening space and season.
Care of fall crops Top
The beginning of fall garden care comes when the weather and the radio station announce the first arrival of frost. Your main concern then should be to harvest all ripe, tender crops. Tomatoes, summer squash, melons, eggplant, cucumbers, peppers, and okra are some of the crops that cannot withstand frost and should be picked immediately. Store the vegetables in a place where they can be held until needed for eating or processing. If the frost warning is mild, predicting no lower than a 30 F., try covering tender plants in your garden that still hold an abundance of immature fruit. Baskets, burlap, boxes, blankets, or buckets help protect them from the frost. Warm days after the frost will still mature some of the fruit as long as the plants have this nightly frost protection. Much will depend on the garden's microclimate. If your spot is low and unsheltered, it is likely to be a frost pocket. Gardens sheltered from winds and on the upper side of a slope are less susceptible to early frost damage.
When using a cold frame to extend the harvest season, be sure to close the top on frosty nights to protect the plants from the cold. When the sun comes out the next morning and the air warms, open the cold frame again; leave it closed if daytime temperatures are low.
Cool-season crops such as cabbage, cauliflower, broccoli, spinach, and Brussels sprouts can withstand some cold. In fact, their flavor may be enhanced after a frost. They cannot stay in the garden all winter, but do not need to be picked immediately when frost comes. Kale, spinach, evergreen bunching onions, lettuce, parsley, parsnips, carrots, and salsify are some crops that may survive all winter in the garden. Mulch these overwintering vegetables with 8 inches of mulch to prevent heaving of the soil. Most of these vegetables can be dug or picked as needed throughout the winter or in early spring.
Now is the time to prepare perennial vegetables for winter, too. Most will benefit from a topdressing of manure or compost and a layer of mulch, which reduces damage from freezing and thawing. Dead leaf stalks of perennial vegetables such as asparagus and rhubarb should be cut to the ground after their tops are killed by frost, though some people prefer to leave asparagus stalks until late winter to hold snow over the bed.
When tender crops have been harvested and overwintering crops cared for, pull up all stakes and trellises in the garden except those stakes that are clearly marking the sites of overwintering plants. Clean stakes and trellises of remnants of plant materials and soil. Hose them down and allow to dry. Tie stakes in bundles and stack them so that they won't get lost over the winter. If possible, roll up wire trellises and tie them securely. Store these items inside your attic, barn, or shed in an area where they are out of the way, and where rodents and other animals cannot get to them to use as winter nests.
Preparing soil for winter Top
Now you are ready to prepare the soil for winter. Pull up all dead and unproductive plants and place this residue on top of the soil to be tilled under, or in the compost heap. Remove any diseased or insect-infested plant material from the garden that may shelter overwintering stages of disease and insect pests. If this plant material is left in the garden, you are leaving an inoculum of diseases and insects which will begin to reproduce the next spring and add to your pest problems.
The best thing to do is to remove infested plant material from the garden or burn it. Burning will kill any diseases or insects that may be in plant wastes. Spread the ashes on the garden to get the benefit of mineral nutrients. Check laws in your area before burning anything; you may need a permit. If you live near a wooded area, burning may be too risky. In this case, haul the diseased material away.
Clean-up also gives you the chance to add compost to the garden. Compost contains highly nutritious, decomposed plant material and beneficial organisms, and is an excellent soil-builder. By spreading compost and other wastes on the soil and plowing them in, you are adding nutrients to the soil for next year's crop. The beneficial insects and microorganisms in the compost will help integrate the compost with the soil, and the added humus will improve soil structure.
Don't overlook other excellent sources of organic material available during the fall. Leaves are abundant, and neighbors will usually be glad to give their leaves away. Put some on the garden now and store some for next year's mulch. Leaves will mat if put on in too thick a layer, and will not decompose quickly. You can help leaves break down more easily by running a lawn mower back and forth over the pile. Put the shredded leaves directly onto the garden or compost them. Many farms and stables want to get rid of manure piles before winter sets in. All these sources of organic matter will benefit soil conditions.
If you wait until just before planting to add organic material to the garden, it may not have time to decompose and add its valuable nutrients to the soil by the time you are ready to plant, and you may have to delay planting to a later date. Hot (very fresh) manure can also burn young seedlings. By adding these materials after harvest, you give them plenty of time to decompose and blend into the soil before planting time. If you don't have enough organic material for the entire garden, try to cover those areas that you want especially rich for the next gardening season.
If the weather stays dry enough before the ground freezes, you can plow or rototill in the fall. Turning under vegetation after harvest allows earlier planting the next season and is especially good for heavy soils, since they may be exposed to the freezing and thawing that takes place during the winter. This helps to improve soil structure. If you have a rainy fall, or if the garden is steep and subject to erosion, you may decide you'd rather plant a cover crop to protect the garden. A cover crop decreases erosion of the soil during the off season, adds organic material when it is incorporated prior to planting, improves soil tilth and porosity, and adds valuable nutrients. Off season cover crops should be planted early enough to make some growth before hard frost kills them. Where you have fall/winter crops growing, you can sow cover crop seed between rows a month or less before expected harvest. This way the cover crop gets a good start, but will not interfere with vegetable plant growth.
Prepare the soil for cover crop seed by tilling under plant wastes from the last crop. Ask at the seed store what the best type of cover crop for your area is and at what rate (pounds per 100 square feet) to plant it. Broadcast the seed, preferably before a rain, and rake it evenly into the soil. Planting may be delayed somewhat by the practice of cover cropping, since time must be allowed for the green manure to break down. If you have crops that need to be planted very early, you may prefer to leave a section of the garden bare or with a stubble mulch.
When time or weather conditions prohibit either tilling or cover cropping, you may wish to let your garden lie under a mulch of compost, plant wastes, or leaves all winter to be plowed or tilled under before planting. However, if you want to plant early, a mulch of heavy materials such as whole leaves may keep the soil cold long enough to delay planting. In this case, chop them fine enough that they will break down during the off season. The addition of fertilizer high in nitrogen will also help break down organic matter more quickly.
Some cover crops suitable for winter use are in the table 10.14. Mixtures of legumes and non-legumes are effective as well.
Care of garden equipmentTop
Clean-up of tools and equipment is another important practice related to the garden which should not be ignored in the fall. Proper clean-up of tools now will leave them in top shape and ready to use when spring comes. Clean, oil, and repair all hand tools. Repaint handles or identification marks that have faded over the summer. Sharpen all blades and remove any rust. Power tools should be cleaned of all plant material and dirt. Replace worn spark plugs, oil all necessary parts, and sharpen blades. Store all tools in their proper place indoors, never outdoors where they will rust over the winter.
Unless you are lucky enough to live in a warm area where a cold frame will protect vegetables all winter, you will need to clean up the frame when all vegetables have been harvested. Remove all remaining plant material and spread it on the cold frame soil. Spade the plant refuse and any other organic material into the soil in the cold frame as thoroughly as possible. Do not leave the top on the cold frame over the winter, as the cold air or the weight of snow may crack or break the glass. Remove the top, wash it thoroughly, and store it on its side in a protected indoor area where it will not get broken.
Successful gardening doesn't stop when frost comes, but continues throughout the fall and early winter months. When following good garden care practices during this time, your garden will be ready for the growth of healthy vegetables next spring.
Table 10.14


Type Legume/Non-Legume Amount to Sow Per 100 ft./(oz.) When to Sow When to Turn Under Effects Notes
Alfalfa L 1/2 - 1 Spring
Late summer
Fixes 150-250 lbs N/ac/yr; deep roots break hard soil. Loam, fairly fertile soil. Needs warm temps for germination. Drought tolerant. Hardy. Perennial. Can be hard to control. Inoculate seed.
Barley N 3 Fall
Adds organic matter; improves soil aggregation Annual. Prefers medium rich loam soil. Not as hardy as rye. Tolerates drought.
Buckwheat N 1 1/2 Spring
Mellows soil rich in potassium Annual. Not frost tolerant. Grows quickly
Sweet Clover L 1/2 - 1 Spring
Fixes 100 - 150 lbs N/ac. Biennial. Inoculate seed. Greatest benefit is in second year.
Fava Beans L 5 /plant 8" apart Early Spring
Late Summer
Early Summer
Some types fix 70 - 100 lbs in little as 6 wks. Use small-seeded rather than table types. Annual. Adapted to many soil types. Medium drought tolerance. Likes cool growing weather. Inoculate with same bacteria as for hairy vetch.
Oats N 3 Spring
Adds organic matter, improves soil Annual. Needs adequate manganese. Not hardy.
Rye, Winter N 3 Fall Spring Adds organic matter, improves soil aggregation. Annual. Very hardy. Can plant later than any other cover crop.
Vetch L 2 Early Fall Spring Fixes 80 - 100 lbs N/ac/yr Annual. Inoculate seed. Hairy. Slow to establish. Fairly hardy. Till under before seeds can become a weed.
Wheat, Winter N 3 Fall Spring Adds organic matter; improves soil aggregation. Same as barley.

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