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- Chula Vista, CA
What can I do to make my orange tree produce sweeter oranges? I don’t know the variety. They are just too tart. The tree is full of oranges and I also see many new buds. Should I leave them on the tree longer? Is there anything I can add to the soil?
- Oakland, OR
One important factor in producing sweet oranges is heat. You need moderate to high heat to form naturally sugars that make the oranges taste sweet; sour types need much less heat. Hopefully what you have is a Valencia as this type has lower heat requirements and therefore better suited to your area.
Navel varieties typically produce fruit in November and December, whereas Valencias are ready to harvest anytime from January into May, depending on the variety. Leave the buds on the tree--most of the flowers won't result in fruit and will eventually fall off. You can encourage more of the flowers to become fruit by ensuring the tree's moisture requirements are met, especially during and immediately after flowering. Full sun will also result in better-tasting fruit, as will feeding the tree with the proper nutrients, which include trace minerals such as iron, magnesium, copper, zinc, manganese and a few others. Use an organic fertilizer for citrus (or one with 10-10-10) and feed as directed throughout the growing season, or use compost or aged manure, or a combination of the two. I also recommend rock dust, which provides trace minerals that help put more flavor into the fruit. If at the end of doing this you still have sour-tasting oranges, then you have a sour orange tree and I recommend making orange marmalade!