How often during spring & summer should I apply Tui Citrus Food fertiliser? Fortnightly, monthly, every 6 months? 

• Apply Tui Citrus Food in spring and again in late summer early autumn, feed citrus in the growing season when plants are actively growing. 
• Citrus are a sub-tropical fruit trees and so can be frost tender in some areas. 
• Apply citrus food in spring when the risk of frost has passed (August, September).
• If applied too early in spring soft new growth will emerge that hasn't had time to harden off and so will be damaged by frost.
• Feed citrus again in late summer, early autumn (January, February).
• Avoid feeding too late into autumn in frost prone regions as new growth won't have had time to harden off and so can be damaged by frost.
• In frost free regions you can feed anytime in spring through to autumn.
• If your citrus does get frost damage, do not remove the damaged foliage until frosts have finished as pruning will push soft new growth. 
• Throughout the growing season, spring, summer and autumn, supplementary feed weekly with Tui Citrus & Fruit Superfood liquid fertiliser to boost growth and correct any nutrient deficiencies that can cause yellowing of leaves.