Citrus unshiu 'Okitsu' (Mandarine)
- Herman Kraut
- Sep 24
- 4 min read
Common Name: Tangerina Okitsu, Satsuma ‘Okitsu’; Okitsu wase; marketed as mandarin
Scientific Name: Citrus unshiu 'Okitsu'
Plant Family: Rutaceae
Lifecycle: Perennial
The Tangerina Okitsu is a prized satsuma mandarin variety, known for its seedless, sweet, and early-ripening fruit. Growing Citrus unshiu 'Okitsu' in Zone 8a offers homesteaders a reliable citrus that tolerates light frost better than many oranges, making it an excellent choice for Mediterranean-style food forests. While patience is required in the early years, Okitsu tangerines shine in flavor and ease of peeling.
For in-depth guides and curated tools, be sure to check out our Recommended Books & Resources section below.
Plant Profile
Characteristic | Information |
Climate Suitability | USDA Zones 8–11; Köppen Csa (hot dry summers, mild wet winters) |
Sun / Shade Needs | Full sun, minimum 6 hours per day |
Watering Needs | Moderate; deep soak weekly in summer, taper in winter |
Soil Preferences | Well-drained sandy or loamy soil; pH 6.0–7.0 |
Spacing & Height | 3–4 m spacing; 2.5–3.5 m height and spread |
Propagation Method(s) | Grafted onto trifoliate orange or sour orange rootstock |
Planting Timeline | Autumn in mild areas or spring after frost risk |
Companion Plants | Prickly pear, comfrey, rosemary, legumes, yarrow |
Edible / Medicinal / Ecological Uses | Fresh eating, juice, vitamin C rich; citrus bloom supports pollinators |
Pest / Disease Considerations | Citrus leaf miner, scale, aphids; monitor for rootstock suckers |
Pruning / Harvest Notes | Light winter prune; remove suckers; harvest Oct–Dec when skin brightens |
Quick Plant Reference
Care Level: Moderate
Optimal Sunlight: Full sun (6–8 h)
Water Needs: Weekly deep watering during dry spells; mulch to conserve moisture
Mature Size: 2.5–3.5 m (8–12 ft) tall and wide
Soil Type: Light, well-draining, slightly acidic to neutral
Humidity: Medium
Toxicity: Non-toxic to humans; peels fine for compost
Beneficial Pollinators: Honeybees, native bees, hoverflies
Health Benefits: High vitamin C and flavonoids; low acidity for easy eating
Chilling Hours: ~100–200 h below 7 °C (45 °F)
Pollination Requirements: Self-fertile
Our Citrus unshiu 'Okitsu' Application @ Tough Kraut
Planted on November 15, 2022, our Citrus unshiu ‘Okitsu’ sits east of the black mulberry at the start of a north–south treeline. Like our other citrus, growth has been slow and there are no flowers or fruits yet. We prune lightly, remove water shoots around the main stem, and MuDan has tied one branch down to a stone to open the canopy for airflow and better light. The goal is a wider, sturdier framework before fruiting begins.
Step-by-Step Growing Guide
1. Choose the Right Site
Warm, wind-sheltered, full-sun spot with good air movement. Avoid frost pockets and heavy shade.
2. Prepare the Soil
Incorporate compost into sandy-loam. Aim for pH 6.0–7.0 to keep nutrients available. Build a shallow mound on heavier ground.
3. Plant the Tree
Set the graft union about 5 cm (2 in) above the final soil line. Backfill gently, water to settle, then mulch as a donut, not a volcano.
4. Water Consistently
Deep soak weekly in summer. Reduce in winter to prevent root issues. Prioritize infrequent, thorough irrigation over frequent sips.
5. Ensure Proper Pollination
Self-fertile, yet nearby flowering herbs and other citrus boost bee traffic and set.
6. Prune Annually
Late winter tidy. Remove crossing wood and water shoots. Keep an open center for light penetration and quick leaf drying.
7. Manage Pests and Diseases
Scout tender flush for leaf miner. Treat early aphids and scale with neem or horticultural soap. Keep mulch fresh and off the trunk.
8. Harvest and Store
Once mature, expect October to December harvests. Fruit keeps 1–2 weeks at 4–8 °C (39–46 °F) or juice and freeze.
9. Note
Slow early growth is normal. Check for rootstock suckers, soil compaction, and watering depth before changing nutrition.
Kraut Crew Insight
Roots before fruits. The low-drama routine of deep water, mulch, and gentle training has our Okitsu building bones now for sweetness later. Small tweaks, big compounding results.
Photos
Herman’s Tough Kraut Field Notes: Solving Citrus unshiu 'Okitsu' (Mandarine) Challenges
Troubleshooting and FAQ are part of the satsuma journey. Here are the fixes we lean on in Zone 8a.
Q: No flowers after a few years. Is something wrong?
A: Satsumas commonly take 3–5 years to settle. Stay consistent with deep watering, keep nitrogen modest, and focus on structure.
Q: Leaves curl or look blistered on young flush.
A: Often citrus leaf miner. Prune the worst tips, encourage flush during cooler periods, and apply neem or kaolin on new growth cycles.
Q: Light frost coming. Protect or not?
A: Okitsu tolerates cold well for citrus, but young trees benefit from a frost cloth on predicted cold nights. Remove covers in the morning.
Q: Branches are upright and crowded.
A: Keep tying a few limbs outward like MuDan did. This increases airflow, sunlight, and future fruiting wood.
Q: Yellowing between veins on new leaves.
A: Possible micronutrient lock from high pH. Use chelated iron as a foliar in spring and top up composted organic matter.
Recommended Books & Resources
Books
How to Grow Citrus Practically Anywhere by Darren Sheriff (“The Citrus Guy”)
Short, practical playbook for container culture + cold protection outside the classic citrus belt — exactly the edge most Zone 8a growers need for satsumas.
The Lazy Gardener’s Guide to Growing Citrus in Containers by Trey Watson
A concise, beginner-friendly manual that strips container citrus down to what actually works: soil mix, watering cadence, and simple overwintering. Perfect for readers who want fruit without fuss.
Citrus: How to Grow and Use Citrus Fruits, Flowers, and Foliage by Monica Brandies
Slim, colorful booklet that mixes grower tips with practical uses (peels, blossoms, recipes). Great for rounding out your satsuma entry with low-waste kitchen and apothecary angles.
Field Guide to Citrus Pests by Gregg Stephens
A compact, image-forward ID guide that helps homesteaders quickly separate leafminer vs. scale vs. thrips and choose sensible controls — handy for IPM-minded readers.
Citrus at Home: A Complete Guide to Homegrown Citrus Trees by Olesia Naumchyk
A newer indie title focused on variety selection for small spaces, light, and watering basics; useful as an approachable on-ramp for first-time citrus keepers.
Resources
Yellow Sticky Traps (6×8 in, dual-sided)
For early detection of whitefly/leafminer flights around citrus. Low cost, easy win for IPM.
Tough Kraut Resources
Our hand-picked citrus essentials — from slow-release watering bags to neem oil — the same tools we rely on to keep our satsuma trees healthy.
Entry last updated: 2025-09-20
This post is part of the Tough Kraut Plant Library, documenting what really grows on our off-grid homestead in Central Portugal.
Comments