Oxalis ‘Iron Cross’ (Oxalis tetraphylla), often called Lucky Clover, is a popular plant known for its distinctive four-leaf clover-shaped foliage, featuring vibrant green leaves with a prominent deep purple or maroon cross pattern at the center of each leaflet. Its unique appearance and straightforward care make it a favored choice for indoor and garden displays, despite not being a true clover.
Everyday Care Essentials
Light
Oxalis ‘Iron Cross’ thrives in bright, indirect light. It tolerates some direct morning sun, but intense afternoon sun can fade leaf markings or scorch foliage. A west or south-facing indoor window often provides suitable light.
Watering
Water when the top inch or two (2-5 cm) of soil feels dry. Allow soil to dry slightly between waterings to prevent bulb rot. Overwatering commonly leads to root problems.
Soil
Oxalis ‘Iron Cross’ requires a well-draining soil mix. A suitable blend includes standard potting soil with amendments like perlite, sand, or coco fiber for improved drainage and aeration. It adapts to various free-draining soil types.
Temperature & Humidity
Oxalis ‘Iron Cross’ prefers average room temperatures, between 15°C and 24°C (59°F and 75°F). It is not frost-tolerant; bring indoors or protect in climates below 15°C (60°F). Normal indoor humidity is usually sufficient, requiring no special adjustments.
Fertilizing
During spring and summer, fertilize every 2 to 4 weeks with a balanced liquid fertilizer, diluted to half strength, to promote healthy growth and vibrant blooms. A slow-release fertilizer can also be applied at the season’s start. Reduce or stop fertilizing during fall and winter when growth naturally slows.
Navigating Dormancy
Oxalis ‘Iron Cross’ has a natural dormant period, often in winter or hot summer months. Leaves yellow and die back, signaling a resting period. This natural cycle is necessary for the long-term health and vigor of bulbous plants.
As foliage declines, gradually reduce watering and cease fertilization. Once leaves die back, store bulbs in a cool, dark, dry location like a basement or closet. This resting period lasts two to three months. After this, replant bulbs and gradually resume watering to encourage new growth, restarting the cycle.
Planting, Repotting, and Propagation
Planting
Plant Oxalis ‘Iron Cross’ bulbs 2.5-5 cm (1-2 inches) deep with the pointed end facing upwards. Space multiple bulbs 10-12 cm (4-5 inches) apart for adequate growth. Planting is best done in spring, aligning with its natural growth cycle.
Repotting
Repot Oxalis ‘Iron Cross’ every two to three years, typically in spring. This refreshes the soil and provides more space for growing bulbs. Choose a new pot only slightly larger (2.5-5 cm or 1-2 inches wider) to prevent soil from remaining too wet.
Propagation
Propagate Oxalis ‘Iron Cross’ by dividing its bulbs. Do this during dormancy or when repotting. Remove the plant, gently separate bulbs, and plant them into new containers with fresh, well-draining soil.
Troubleshooting and Safety
Troubleshooting
While robust, Oxalis ‘Iron Cross’ can have issues. Yellowing leaves often indicate overwatering or dormancy. Allowing soil to dry between waterings prevents root rot. Outdoors, it may be susceptible to slugs and snails. Rust diseases are less common but can affect Oxalis.
Safety
Oxalis ‘Iron Cross’ contains calcium oxalates. While edible for humans in moderation, it is mildly to severely toxic if ingested by pets (dogs, cats, horses). Pet symptoms include vomiting, drooling, and loss of appetite. Keep this plant out of reach of curious animals.