2.3. Temperature trials
One hundred and fifty stones from each of the five cultivars were individually cracked and the seeds stratified as above. After stratification, the seeds of each variety were placed in 50 mm pots containing Debco General Growing Mix then randomly divided into five aliquots, each totalling 30 seeds. Four of the aliquots from each cultivar were placed in Thermoline growth cabinets at 10, 15, 20 or 25 8C with a 13 h photoperiod. The fifth aliquot of seeds was placed in a shadehouse and the plants grown at ambient conditions. At weekly intervals, plant height was recorded