Garden Scheme
Perilla frutescens
Shiso is a leafy annual herb that builds a compact but noticeable presence in a summer planting, reaching about 2½ feet tall and 1½ feet wide. Its aromatic, serrated foliage gives it enough visual weight for the middle of an herb bed or the front half of a mixed edible border. Plan for foliage harvest from summer into fall, with flowering beginning late in the season.
Space Shiso 12 inches apart, measured center to center (30 cm).
The mature spread is about 18 inches (45 cm), so plants set at that distance grow together into a closed canopy over the bed.
Treat 12 inches as a planning baseline — cultivar and local growing conditions shift the final footprint.
Place shiso where it receives full sun and can be reached easily from a path or bed edge for repeated harvest. Its upright, leafy form works well behind low herbs and in front of taller warm-season crops, without needing a trellis or other support. Use a block or short row rather than scattering single plants through a tightly planted bed, so volunteer seedlings can be spotted and managed before they crowd nearby plants.
Set plants 12 inches apart, center to center, for a close harvestable planting. At maturity, each plant can spread about 18 inches wide, so the foliage may knit together; leave one open side beside a path or stepping space when possible. Keep the planting set back from narrow circulation routes, since the leafy canopy can lean into the edge of a bed as summer growth fills in.
Use a full-sun site and provide moderate water through the growing season. A fertile, well-drained bed suits shiso best; avoid reserving a low pocket that stays waterlogged after rain. In a raised bed, place it away from the driest outer edge if that area is difficult to water consistently.[1]
Shiso occupies its space as an annual, with foliage available in summer and fall. Late-summer to early-fall flowers extend the planting into the transition season and can bring pollinator activity to an herb bed. Leave enough access around the clump for harvest before the planting becomes denser late in the season.
Reserve shiso for a contained garden bed rather than an edge adjoining unmanaged ground. It can self-seed readily, and flowering plants can produce a new crop of seedlings beyond the intended footprint. Remove flower spikes before seed set when spread is not wanted, and inspect the bed early the following season so unwanted seedlings do not take over spaces planned for other annuals.[1]