Another cool-season crop, lettuce tends to bolt when summer highs consistently top 21°C. Fortunately, high-yielding leaf lettuce matures quickly so there’s still time to enjoy a bountiful second harvest once the worst of the summer heat has passed—picking the outside leaves of heat-tolerant loose-leaf types begins long before the plant’s maturity date.
Lettuce seed sown in mid- to late summer at two week intervals will supply you with salad greens until autumn; sow your final crop about 35 days before the first expected frost date in your region. Because lettuce is mostly water, it’s intolerant of drought; water regularly during dry spells.
Quick tip: Lettuce should be harvested regularly and frequently: Once plants have matured they quickly lose their flavour and nutritive value.
Loose-leaf lettuces for late-summer and autumn harvests (43 to 55 days)
- 'Bergam’s Green'
- 'Green Salad Bowl'
- 'New Red Fire'