Stock Flower (Matthiola) Seeds

Stock (Matthiola incana) is a fragrant cool-season ornamental from the Mediterranean basin, prized for its tall, densely packed flower spikes and that unmistakable sweet, clove-like perfume. The blooms range across soft pastels and richer shades, making them a favourite for winter borders and as long-lasting, beautifully scented cut flowers for the home.

Planting

Sow seed shallow, about 0.6 cm deep, covering only thinly since Stock needs light to germinate well; sieved compost or vermiculite that lets light through works best. Keep the medium evenly moist at around 18-24 C and seedlings appear in 7-14 days. Start indoors roughly 5-10 weeks before transplanting, pricking seedlings into pots once they have two true leaves. Grow in full sun with 6+ hours of direct light. For cut flowers, space plants 10-15 cm apart with netting for straight stems; thin garden plantings to about 25 cm for airflow.

Fertilizing

Test the soil before amending. Avoid excess nitrogen, which produces weak, floppy stems. Watch for potassium deficiency, which shows as brown leaf tips and margins at flowering, and supply adequate potassium through the growing and flowering phase. Stock prefers neutral-to-alkaline soil (pH about 6.0-8.0) and does poorly in acidic ground.

Care

Keep soil consistently moist but well-drained, watering at the base rather than the foliage to limit disease. Pinch out the growing tip of branching column types for bushier plants with more spikes. Watch for aphids, thrips, flea beetles, and diamondback moth, plus powdery or downy mildew in mild, damp winters. Harvest cut stems when one-third to one-half of the florets are open; stems do not regrow after cutting.