“Citrine plant” is not a scientific botanical term. It typically refers to plants whose appearance, especially their fruit, evokes the warm, yellow-orange color of citrine. The Citrus medica, widely known as the Citron, is the most likely plant people are searching for when using this term, given the similarity in names and the distinct yellow rind of its fruit. This ancient citrus species is one of the original fruits from which many other citrus types developed. The term can also broadly encompass various plants featuring yellow or orange tones in their leaves, flowers, or fruits.
Citron Plant Characteristics
The Citron plant (Citrus medica) is an evergreen shrub or small tree, generally reaching a height of 8 to 15 feet. It typically has irregular, straggly branches, often adorned with long, sharp thorns. Its leaves are evergreen, ovate-lanceolate, lemon-scented, and often display slightly serrated edges and a wavy margin.
The plant produces fragrant white or purple-tinged flowers in clusters. The fruit of the Citron is its most distinguishing feature; it is large and oblong, sometimes ribbed or even fingered in varieties like ‘Buddha’s Hand’. The rind is thick, aromatic, and turns yellow when ripe, containing minimal pulp and often many seeds. The pith, or albedo, is thick and white, and it is the primary part used.
Cultivating Citron Plants
Growing Citron plants successfully requires attention to specific environmental factors. They thrive in warm, humid conditions and are sensitive to cold and frost, making them suitable for USDA Zones 10–11. In Zones 8–9, they can be grown in containers and brought indoors during colder periods. Optimal temperatures for their growth range from 15°C to 27°C (59°F to 80°F), with growth ceasing below 13°C (55°F) and above 35°C (95°F).
Citron trees need ample sunlight, receiving at least 6 to 8 hours of direct sun daily. If grown indoors, they benefit from bright, direct light for 10-12 hours per day, sometimes supplemented with grow lights. The soil should be well-drained, loamy, and have a slightly acidic to neutral pH (5.5–7.0). For container growing, a citrus-specific potting mix enriched with sand or perlite improves aeration and drainage.
Keep the soil evenly moist but not waterlogged. Water deeply when the top inch or two of soil is dry, reducing frequency in winter. Proper drainage is crucial to prevent root rot, so pots must have drainage holes. Citron plants are heavy feeders and benefit from regular fertilization during the growing season (spring through fall). Apply a balanced citrus fertilizer, typically with a 5-2-6 nutrient composition, rich in nitrogen and micronutrients like magnesium and iron, every 4-6 weeks.
Beyond Citron: Other Plants with Citrine Hues
While the Citron plant is a direct fit for the “citrine plant” descriptor, many other plants exhibit beautiful yellow or orange tones. These colors appear in vibrant flowers, striking foliage, or ripe fruits. Examples include marigolds, known for their bright orange and yellow blooms, and sunflowers, which feature large, golden-yellow petals. Certain varieties of coleus plants also display rich orange and yellow patterns. Additionally, fruits like lemons, oranges, and some peppers naturally showcase citrine shades as they mature.
Uses and Cultural Significance of Citron
The Citron fruit has a long history of diverse uses, primarily centered around its thick and aromatic rind. Unlike other citrus fruits, its pulp is often minimal and dry, with its value lying in its fragrant peel. The rind is frequently candied to create succade, a popular ingredient in desserts, fruitcakes, and preserves. Citron zest also flavors baked goods, whipped cream, and liqueurs.
Beyond culinary applications, Citron has played a role in traditional medicine, historically used to address issues like seasickness, nausea, and indigestion. It is recognized for its pectin and vitamin C content, with its extracts showing potential antioxidant and anti-inflammatory properties. Culturally, the Citron holds significant religious importance, particularly the ‘Etrog’ variety, central to the Jewish festival of Sukkot. In some Asian cultures, varieties like ‘Buddha’s Hand’ are used as spiritual offerings, symbolizing longevity and happiness.