Germination temperature
Warm: about 25 °C (77 °F) gave the best result in a laboratory study (tested range 20-30 °C, 68-86 °F).
Herb growing guide
Common sage is a long-lived, woody kitchen herb that is easy to raise from seed if you sow it shallowly, keep it warm and give the plants sharp drainage. Expect the first proper harvest in the second year.
Warm: about 25 °C (77 °F) gave the best result in a laboratory study (tested range 20-30 °C, 68-86 °F).
Very shallow: a thin layer of fine compost, about 2 mm (1/16 in).
About two weeks.
Light helped germination in trials; keep the cover thin and the tray bright.
None needed. Fresh seed can be partly dormant; older dry-stored seed often germinates better.
Start in pots or modules and transplant.
Sow two or three seeds per small pot or module and keep the strongest seedling. Sage seed is round and easy to handle, so there is no need to mix it with sand.
Not needed. The seed coat does not block water uptake.
Not needed. Sage germinates without a cold period.
Not needed. In a trial, 24-48 hours of rinsing in running water did not improve germination of fresh seed or emergence in the field.
Keep the pots warm, ideally around 25 °C (77 °F). Use a propagator, or cover the pot with a clear bag on a warm windowsill. In India, sow at the end of the hot season or in the mild post-monsoon months rather than during the peak heat.
Barely cover the seed. In a net-house trial, emergence fell steadily as sowing depth increased from 2 mm to 5 mm and 10 mm.
Moist, fine, free-draining seed compost (peat-free where possible).
Keep the compost evenly moist but never wet. Remove the clear cover as soon as seedlings appear to avoid damping off.
Continuous light gave the best germination in the laboratory study, so a thin cover and a bright position help. Once up, seedlings need full light to stay compact.
Usually about two weeks. Fresh seed may germinate slowly and unevenly because some of it is dormant.
Move seedlings into larger pots as they grow and keep them warm and bright until they are bushy young plants.
Plant out in full sun in free-draining soil, at least 30 cm (12 in) apart. For containers use a pot at least 30 cm (12 in) wide and deep with drainage holes, soil-based compost and up to a quarter grit.
Pick only a few leaves in the first season. Seed-raised sage needs at least a year to reach a size worth harvesting regularly.
Cause: seed buried too deep, a cold pot, or fresh dormant seed. Fix: cover very thinly, keep near 25 °C (77 °F) in a bright spot, and give the tray a full two to three weeks.
Cause: damping off in wet, airless compost. Fix: water lightly, remove the cover once seedlings appear, and give good air flow.
Cause: waterlogged soil around the roots. Fix: grow in raised beds or pots with grit, and never let water stand around the plant.
Cause: rosemary beetle, sage leafhopper or capsid bugs. Fix: damage is usually light; pick off the beetles and the worst leaves.
Cause: powdery mildew. Fix: give plants space and sun, and remove badly affected shoots.
Sage is drought tolerant once established. Water in long dry spells and in pots, but let the soil dry between waterings; rich, wet soil gives soft growth and weaker flavour.
Trim lightly in mid to late spring to keep plants compact, and cut off faded flower stems in late summer. Never cut back into bare old wood, which may not resprout.
Pick young shoots or single leaves as needed; growth in spring and summer has the best flavour. Hang sprigs to dry in a warm, dark, airy place or freeze chopped leaves.
After six or seven years sage becomes woody and straggly. Root softwood cuttings in late spring or early summer, or layer a stem, to keep young plants coming.
Sow sage shallowly in warm, bright conditions for a long-lived kitchen herb.
About two weeks in warm compost. Fresh seed can be slower and patchier because part of it is dormant.
Only very thinly. Light helps germination and emergence drops when seed is sown deeper than a few millimetres.
It needs very sharp drainage and full sun. Grow it in pots or raised beds with grit, sow outside the peak heat, and keep it out of standing water during the monsoon.
Take only a few leaves in the first year; plants raised from seed need at least a year to reach full harvesting size.