ENSURING A GOOD CROP

Soil fertility is important for crop maturation as well. Low fertility results in slow growth. Excess nitrogen causes too much vegetative growth and delays maturity. High phosphorus hastens maturity.

Plant population also has an affect on crop maturity. A low plant population matures slightly earlier than a denser population. Plants requiring a long season are best spaced to the maximum distance recommended; while, with short season crops such as radishes, the minimum can be used.

Soil type plays its part too. Sandy soils warm up sooner in the spring but cool off faster in the fall. Clay is just the opposite. So it is seen that a good humusy soil will give a longer season of growth. But too much raw organic matter results in frost retention for a longer period in the spring. Any organic matter added to the garden in the fall should be well rotted.

Soil temperature is as important, if not more so, than air temperature. It affects the germination of the seeds. Plants can survive at lower air temperatures if the soil temperature is kept to the proper level.

Soil moisture must be present at seeding time or germination and therefore growth will be delayed. If snowfall or spring rainfall is scanty, avoid working the soil too much before planting. Just keep the surface worked to provide a mulch to prevent evaporation.

Photoperiodism is another factor governing the growth of plants. Longer periods of daylight reduce the amount of heat required to mature the crop. This is one place where the north has the edge over the south. Spring and summer days are very, very long. At Fairbanks, Alaska, from May 24 to August 30, the hours of sunlight and twilight each day equals 24 hours. Twilight has sufficient light intensity to affect photoperiodic responses and probably some photosynthetic activity. These long hours of daylight give Fairbanks a potential of 430 hours more sunlight than Chicago or the equivalent to 36 twelve-hour days. With the proper selection of cultivars and techniques to improve soil and air temperatures, the yield of vegetables in Alaska greatly exceeds the U.S. national average yield and even the yields of some of the best producing areas of the U.S. This dramatically shows the benefits of northern production of cool weather crops. But some crops cannot tolerate the rapid growth under the long hours of sunlight. Beets and spinach varieties tended to bolt to seed rather than form marketable plants. They found that planting in cold soil increased this bolting tendency. Cultivars should be chosen that avoid this tendency. Boltardy beets and Marathon spinach are two cultivars that do not have this problem.

Pollination is also essential for many crops. To ensure pollination growers often situate beehives in or near the crop or orchard. In the north pollination is often hit or miss in the home garden. Even when the proper cultivars are present for cross pollination, when required, poor crops may still result. Bees will not fly in high winds and in areas like Beaverlodge, Alberta where the winds blow 85% of the time, this can be a serious problem. Windbreaks are necessary to reduce the wind velocity in the garden or orchard. This subject was discussed earlier. Bees are often hindered by cool, wet weather in the spring. To increase the chances of pollination in the orchard, top-work a few branches of a desired cultivar onto your trees. When growing plants in the greenhouse or when using devices such as the Tomato Hoods, insects are usually not able to pollinate the plants. Pollination must be accomplished by other means. Gently shaking the plants, or using a small brush to transfer pollen are two methods to overcome this problem. The fruit of the tomato plant will often be misshapen if poor pollination results. This can also be caused by other factors such as stress from cool temperatures, excess heat, disease, lack of nutrients and drought.

With the short northern growing season, plant material benefits greatly if competition and stress is reduced. This means controlling weeds and insects, as well as providing the nutrients and moisture required by the plants.

ensuring.html
This page by Pat
updated August 18, 2000

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