Use of bottles filled with water. These can be used to protect tomato plants even in the cold winter weather. It is one method which is inexpensive and effective.Fill 750ml one (1) litre or two (2) litre bottles with water up to ¾ full. Place the bottles upright on the ground every third plant along the row when the plants are still young. Always make sure the bottle neck is 10 cm above the plant top. Raise the bottle as the plant grows to always keep the bottle 10 cm above the plant top by either putting a brick under bottle or by tying the bottles on trellising sticks.
When the temperature drops below freezing, the water in the bottle freezes but the plants stay frost free. Water in the plants has a lot of dissolved minerals in it and will therefore freeze at lower temperatures than water in the bottle which though not pure has less dissolved minerals. When water in the bottles freezes it releases a lot of heat which keeps the air around the tomato plants warmer than the general surrounding area.
Planting in high areas away from valleys, slopes that face the sun are better than slopes facing away from the sun
– Choose a frost-free site with good air drainage.
Sprinkler irrigation can be used to control and protect against frost by irrigating lightly very early in the morning to increase humidity in and around the crop field. Overhead irrigation relies on the fact that heat is released when water turns to ice, must have ice continually forming for true effect.
– Cover plants with plastic or grass during the night and remove to allow sun heat during the day.
– Keep the ground free from weeds and mulch to allow absorption of heat during the day and release of heat during the night.
– Erecting a 1.5 – 2.0m high grass or plastic fence around or on the upslope and sides of the crop, leaving the downside open, is very effective in preventing frost.
– A diversion dam can be made by mounding up soil or even simply stacking hay bales.
– Burn crop residue, old tires or oil very early in the morning around the field as smoke will trap warm air inside it thus keeping cooler air away from the crop. However, this method has to be used with care as this can lead to uncontrolled fires
– Maximize plant health. A healthy, leafy plant will generate some internal heat and reduce the depth of frost burn into the
– Use a generous layers of mulch and straw to planting beds. Mulch, like coarse compost and straw, helps protect soil from pelting rains while insulating soil temperatures. Straw bales are preferable because they continually decompose, and as they do so, they generate heat. You can also just plant on straw bales or place containers and smaller boxes on straw bales for added warmth.