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METHODS TO PREVENT FREEZE DAMAGE
HOW TO PREVENT A RADIATIONAL FREEZE OR FROST
1) Decrease rate of radiational cooling
    a) hot caps or plastic tents
    b) mulches
    c) foams
    d) fog or water vapor 
    e) smoke

2) Increase air temperature
    a) eliminate temperature inversion:
        1) wind machines
        2) helicopters
    b) irrigation
        1) flood irrigation; water is warmer and stabilizes temperature (due to high specific heat)
        2) overhead irrigation; constant temperature at 32 oF when liquid/ice present
    c) oil burners or smudge pots
 

HOW TO PREVENT ADVECTIVE FREEZE DAMAGE
1) Plant selection - the ideal method, because then no other method is needed 

2) Radiational freeze methods - some are moderately effective for mild, short freezes. 
    a) Insulate: mulch, foam, hot caps (NOT fog or smoke) 
    b) Increase air temperature: irrigation, oil burners or smudge pots if mild and little wind 
    c) CANNOT USE: fog, smoke or eliminate temperature inversion

3) Site selection - avoid north side of hills, buildings, etc.; avoid low areas, valleys, etc.

4) Delay development in spring - avoids damage to new spring growth and flower buds 
                                                    from late spring frost.

5) Harden-off or cold acclimation in fall: is a normal part of dormancy and preparation of 
                                                                the plant for for winter. 
    Naturally triggered by: 
    a) short days 
    b) cool temperatures 
    c) cold temperatures 

    Allow to occur naturally by observing the following:
    1) Do not encourage growth:
         a) decrease fertilization 
         b) decrease watering 
         c) avoid pruning 
    2) Avoid stress
         a) insect, disease or physical damage 
         b) poor nutrition and nutrient deficiencies 
         c) too heavy fruit load