Introduction & History

Reinking is a distinguished American pomelo variety that emerged from the University of California's Citrus Research Station in Riverside during the mid-20th century — a time when California was positioning itself as the world's premier citrus breeding ground. Named after the Reinking family of citrus researchers who contributed to its selection, this variety represents the bridge between traditional Southeast Asian pomelo genetics and the demands of Western horticulture. Reinking produces reliably large, sweet fruit with white flesh and a clean, uncomplicated flavor profile that appeals to Western palates accustomed to grapefruit. While it has never achieved the commercial recognition of Chandler or the cult status of Asian varieties, Reinking has quietly proven itself as a dependable pomelo for California's inland valleys, where its moderate cold tolerance and consistent bearing make it a practical choice for the home orchardist seeking a genuine pomelo experience.

History & Origin

Reinking pomelo was selected and named at the Citrus Research Center in Riverside, California, around 1948. The variety was part of the extensive pomelo evaluation program that brought hundreds of Southeast Asian citrus accessions to California for assessment. The Reinking selection stood out for its combination of fruit quality, tree vigor, and adaptability to California's Mediterranean climate. While never widely commercialized, it was maintained in the UCR citrus variety collection and distributed to researchers and serious hobbyists. The variety represents an era when California citrus stations were systematically evaluating world germplasm to identify varieties with potential for American growing conditions.

Botanical Description

A large, upright evergreen tree reaching 7–9 m at maturity, with a broad, rounded canopy typical of pomelo species. Leaves are large (10–15 cm), ovate, dark green, with prominent winged petioles. Flowers are large (3–4 cm), white, waxy, fragrant, borne singly or in small clusters. Fruit is large (14–20 cm diameter, 700–1200 g), pyriform to oblate, with moderately thick rind (1.5–2.5 cm) that ripens to pale yellow. Albedo is white and spongy. Flesh is white to cream-white, organized in large, easily separable segments with intact, juicy vesicles. Flavor is sweet with mild acidity, clean and straightforward. Seeds are large, monoembryonic, variable in number (5–25 per fruit). The tree is vigorous and relatively precocious for a pomelo.

Planting & Cultivation

Select a warm, full-sun location with well-drained soil. Reinking performs well in California's inland valleys on sandy loam to clay loam soils, pH 5.5–7.0. Dig a generous planting hole (80 cm wide, 60 cm deep) and plant grafted trees at the nursery soil line. Do not bury the graft union. Water deeply at planting and apply 8–10 cm organic mulch, keeping mulch away from the trunk. Space trees 5–7 m apart for full canopy development. In frost-prone areas, plant near south-facing walls or structures for heat reflection. Stake young trees loosely for the first year. Irrigate regularly during establishment (first 2 years).

Cultivation

Reinking is relatively straightforward to cultivate compared to specialty Asian pomelos. Fertilize three times annually: early spring (February) with high-nitrogen citrus fertilizer, late spring (May) with balanced NPK, and early fall (September) with potassium-rich formula for fruit quality. Fruit thinning improves individual fruit size — thin clusters to 1–2 fruit after natural drop. Deep, infrequent irrigation suits Reinking well: every 7–14 days in summer depending on soil type. The tree responds well to light annual pruning to maintain canopy shape and improve light penetration. Fruit maturation takes 8–9 months from bloom.

Climate & Cold Protection

Hardy to approximately -2°C for brief periods, suitable for USDA zones 9b–11. Performs best in warm Mediterranean to subtropical climates with hot summers. Inland California valleys (Riverside, San Fernando, San Joaquin) provide excellent conditions with hot days promoting sugar accumulation. Tolerates dry heat well with adequate irrigation. Less demanding of humidity than tropical pomelo varieties. Cool winter nights (5–15°C) during fruit maturation improve flavor without damaging trees. Not suitable for areas with regular freezing temperatures or frost periods longer than a few hours.

Seasonal Care

Spring: Apply nitrogen fertilizer; monitor new growth for leaf miner and aphids; begin increasing irrigation as temperatures rise. Summer: Deep water every 7–10 days; apply balanced fertilizer in May; fruit developing through the hot season. Autumn: Apply potassium-rich fertilizer; reduce watering frequency; fruit approaching maturity; prepare frost protection materials. Winter: Harvest mature fruit (December–February); protect from hard frosts; light pruning of deadwood; reduce irrigation during dormancy.

Cold Protection

Protect from sustained temperatures below -2°C. In California's inland valleys, frost occurs regularly from December through February. Plant on thermal slopes and near south-facing walls. Cover with frost cloth (not plastic) during freeze warnings. Incandescent lights or heat cables in the canopy add 1–2°C. Deep mulch (10–15 cm) insulates roots. Avoid pruning in fall — the full canopy provides natural cold insulation. Young trees need extra protection: wrap trunks and scaffold branches with burlap or foam pipe insulation for the first 3–4 winters.

Seasonal Care Calendar

Propagation

Propagated by budding or grafting onto suitable rootstock. T-budding onto Carrizo citrange or trifoliate orange is recommended for California conditions. Carrizo provides good vigor, Phytophthora resistance, and compatibility. Trifoliate orange increases cold hardiness. Seeds are monoembryonic and produce variable offspring — not recommended for true-to-type propagation. Source budwood from the UCR Citrus Clonal Protection Program or certified nurseries. Grafted trees begin bearing at 4–5 years, with full production at 8–10 years.

Diseases & Pests

In California, disease pressure is moderate. Phytophthora root rot and gummosis are managed through proper drainage and resistant rootstock. Monitor for Asian citrus psyllid (ACP) as part of California's HLB prevention program. Scale insects (California red scale, brown soft scale) are managed through IPM with parasitoid releases. Spider mites can be problematic during hot, dry summers. Citrus leaf miner causes cosmetic leaf damage but rarely affects tree health. Brown rot (Phytophthora) can affect low-hanging fruit after rain — keep fruit off the ground.

Harvesting & Culinary Uses

Harvest when the rind turns from green to pale yellow and the fruit feels heavy — typically December through February in California. Reinking fruit can hang on the tree for several weeks after maturing without significant quality loss, providing a flexible harvest window. Cut fruit with clippers, leaving a short stem. Brief post-harvest curing (1 week at room temperature) can mellow acidity slightly. Fruit stores 2–3 weeks at room temperature, 4–6 weeks refrigerated. Peel and segment for eating — the clean-separating segments are Reinking's best feature.

Culinary Uses

Primarily eaten fresh as a dessert fruit — the white, clean-flavored flesh segments well and pairs with other fruit in platters. Good in pomelo salad (combine with shrimp, mint, chili, and fish sauce for a Southeast Asian classic). Juice is mild and sweet, pleasant in mixed citrus juices. Segments can be added to green salads for textural contrast. The thick rind can be candied, though it lacks the distinctive floral quality of Japanese varieties. Zest is mildly aromatic, suitable for baking applications where subtle citrus notes are desired.

Rootstock Guide

Carrizo citrange is the preferred rootstock for California — it provides Phytophthora resistance, good vigor, and compatibility with Reinking. C-35 citrange offers similar disease resistance with slight dwarfing. Trifoliate orange maximizes cold hardiness for inland valley plantings. Rough lemon produces vigorous trees with large fruit but less cold tolerance. Avoid Volkamer lemon for Reinking — excessive vigor can delay fruiting. Sour orange is an option in alkaline soils but carries tristeza risk in some regions.

Container & Companion Growing

Container Growing

Not ideal for containers due to vigorous growth, but possible in 80–120 L containers for several years. Use well-draining citrus potting mix. Expect reduced fruit size and quantity compared to in-ground trees. Fertilize monthly during the growing season. Move outdoors for maximum summer heat and light. In cold climates, move to a bright, cool indoor location (10–15°C) for winter. Container culture is better suited to smaller pomelo varieties like Valentine.

Companion Planting

Plant low-water Mediterranean herbs like lavender, rosemary, and oregano at the canopy drip line — they attract beneficial insects without competing for water. California native plants like ceanothus and buckwheat support predatory insects. Clover or vetch as living mulch fixes nitrogen and suppresses weeds. Avoid planting near other citrus in ACP-affected areas to limit psyllid habitat concentration. Ornamental grasses provide windbreak without competing for nutrients.

Common Mistakes to Avoid

Neglecting irrigation during California's long dry summers, leading to fruit drop and poor quality. Planting in frost pockets where cold air settles. Over-fertilizing with nitrogen, producing vigorous vegetative growth at the expense of fruit. Failing to thin fruit, resulting in many small, inferior pomelos. Expecting tropical pomelo flavor from a Mediterranean-climate tree — Reinking is excellent but different from Asian-grown varieties. Using excessively dwarfing rootstock that stunts tree growth and reduces fruit size.

Frequently Asked Questions