Frequently Asked Questions About Citrus Trees
1. How much sun do citrus trees need?
Citrus trees require full sun—at least 6 to 8 hours per day. In warm climates, extra sunlight improves sweetness and fruit color. Indoor citrus should be placed in a south-facing window or under grow lights.
2. What soil and pH are best for citrus?
Citrus grows best in well-drained soil with a pH of 6.0–6.5. In clay soils, plant on a mound to improve drainage. Containers should use fast-draining citrus or cactus mix.
3. How do I plant a citrus tree correctly?
Dig a hole the depth of the root ball and 2–3 times wider. Keep the graft union above soil level, backfill with native soil, water deeply, and form a watering basin around the tree. Plant in early spring after frost risk.
4. How far apart should I plant citrus trees?
Standard citrus trees should be spaced 12 feet apart, while dwarf or semi-dwarf trees can be spaced 8–10 feet apart. This prevents overcrowding and ensures good air circulation.
5. When is the best time to plant citrus in California?
The ideal time is early spring once frost danger has passed. This gives the roots time to establish before summer heat. Avoid late fall plantings in frost-prone areas.
6. How often should I water citrus trees in the ground?
In summer, water deeply every 7–10 days. In cooler seasons, water less frequently. Adjust based on soil type—sandy soils need more frequent watering, while clay soils need less.
7. What about watering newly planted citrus trees?
New citrus trees need more frequent irrigation—every 3–7 days depending on temperature and soil. Keep the root ball moist but not waterlogged for the first year.
8. How deep are citrus roots?
Most citrus roots are in the top 24 inches of soil. Deep watering should penetrate this zone to promote healthy root development without waterlogging deeper layers.
9. Should I mulch citrus trees?
Yes—apply 2–4 inches of mulch to retain soil moisture, regulate temperature, and reduce weeds. Keep mulch several inches away from the trunk to prevent disease.
10. How and when should I fertilize citrus?
Feed 3–4 times per year between late winter and mid-summer with a citrus-specific fertilizer containing nitrogen and micronutrients. Avoid fertilizing in late fall.
11. Why are my citrus leaves yellow?
Yellow leaves may indicate nitrogen deficiency, overwatering, or poor drainage. If veins remain green with yellow between, the tree may be lacking iron. Adjust watering and apply balanced fertilizer.
12. Do citrus trees need pruning?
Minimal pruning is required. Remove dead wood, crossing branches, suckers from below the graft, and water sprouts. Light shaping is best in late winter to spring.
13. How do I prevent sunburn on citrus branches?
After pruning, protect exposed branches with a whitewash (interior white latex paint diluted 1:1 with water). This prevents sunburn and bark cracking.
14. Do citrus trees need pollination partners?
Most citrus trees are self-pollinating and do not need a second tree. Bee activity, however, can improve yields.
15. Why do flowers or small fruit drop?
Fruit drop, often called "June drop," is natural. Trees shed excess fruit in late spring. Stress from heat, water fluctuations, or nutrient issues can increase drop.
16. When will my citrus tree produce fruit?
Lemons and limes may fruit in 1–3 years. Oranges, grapefruits, and mandarins typically take 3–5 years to bear well.
17. How long does fruit take to ripen?
Ripening time varies: lemons take 4–6 months, while oranges may take up to a year. Taste fruit rather than relying on color alone, as citrus can remain green but still be ripe.
18. How should I water container citrus?
Water when the top 2–3 inches of soil are dry. In warm weather, containers may need daily watering. Ensure pots drain freely.
19. How often should I repot a citrus tree?
Repot every 2–3 years, refreshing the soil and pruning circling roots. Step up to a slightly larger pot as the tree grows.
20. How do I prevent root and crown rot?
Keep water away from the trunk and graft union. Plant on mounds in heavy soil and ensure good drainage. Never bury the crown.
21. How cold-hardy are citrus trees?
Kumquats and satsumas are the hardiest, tolerating brief dips into the mid-20s°F. Lemons and limes are the most frost-sensitive, often damaged below 30°F.
22. What causes curled, scribbled leaves?
This is citrus leafminer damage. It’s mostly cosmetic on mature trees. Young trees may require treatment during new flushes of growth.
23. What is the black coating on leaves and fruit?
This is sooty mold growing on honeydew secreted by insects like aphids or scale. Control the insects and ants that farm them to eliminate the mold.
24. What common pests affect citrus?
Aphids, scale, mites, thrips, and citrus leafminer are common. Integrated Pest Management (IPM) using horticultural oils and beneficial insects is recommended.
25. What is HLB (citrus greening)?
HLB is a deadly disease spread by the Asian Citrus Psyllid. There is no cure. Buy only from certified nurseries and never transport citrus trees across counties.
26. Should I seal pruning cuts?
No. Sealants are unnecessary and can trap moisture. Make clean cuts just outside the branch collar and allow natural healing.
27. Why do my fruits taste sour?
Sour fruit can result from variety genetics, insufficient heat, shade, or nutrient imbalance. Oranges in cool coastal areas may stay less sweet.
28. Should I let grass grow under citrus?
No. Keep a weed-free zone under the canopy to prevent nutrient and water competition. Mulching is recommended instead.
29. What irrigation system works best?
Drip irrigation or micro-sprayers are ideal. Place emitters away from the trunk and expand coverage as the tree grows.
30. How do I test my soil drainage?
Dig a hole, fill with water, and see how quickly it drains. Good soils drain within 24–36 hours. If water stands longer, plant citrus on a mound.