Repotting guide

When & how to repot Lettuce Leaf Basil (Ocimum basilicum 'Napoletano')

Also called lettuce leaf basil, Neapolitan basil.

More about lettuce leaf basil

About Lettuce Leaf Basil

Ocimum basilicum 'Napoletano' · also called lettuce leaf basil, Neapolitan basil · herb

Lettuce leaf basil is a large-leaved Italian sweet basil whose huge, crinkled, lettuce-like leaves are ideal for wrapping and tearing into salads. A tender warm-season annual, it demands heat, full sun and rich, moist soil, grows vigorously, and is best kept productive by frequent harvesting and pinching out flowers before it bolts.

Mature size: 45-60 cm tall and 30-40 cm wide (18-24 in tall, 12-16 in wide)

Watch for — Frost and cold damage: Like all basil it is frost-tender and blackens below about 10°C. Plant out only after frost has passed and bring potted plants in before cold nights.

How to tell lettuce leaf basil needs repotting

Repotting on a calendar is less reliable than reading the plant. For lettuce leaf basil, watch for these signs:

Roots circling the bottom of the module or pot, or poking out of the drainage holes.
The seedling dries out within a day and growth has visibly stalled.
Roots are white and matted in a tight spiral when you tip the plant out.
It has outgrown its current container for the stage of the season — pot lettuce leaf basil on before it becomes hard root-bound.

For the underlying biology of a pot-bound root system and why it stalls a plant, see our guide to spotting and fixing a root-bound plant.

How often to repot lettuce leaf basil

Pot on seedlings as they grow; not a perennial repot. Lettuce Leaf Basilis grown for one season, so the question is really “how often to pot on” — keep moving it up before the roots circle. A robust, upright tender annual herb with very large, broad, puckered bright-green leaves; sends up white flower spikes that must be pinched off to keep the plant leafy and extend the cropping season..

What size pot to step lettuce leaf basil up to

Pot lettuce leaf basil on gradually — a seedling jumped straight into a huge pot sits in cold, wet, airless soil and stalls. Step up one or two sizes at a time as the roots fill each container, finishing in a large final pot or the ground. The aim is roots that never circle and never check.

Not sure of the exact diameter? Our pot size calculator takes the current pot and root spread and tells you the right next size — it deliberately recommends a single step up, never a big jump.

The best time of year to repot lettuce leaf basil

Pot lettuce leaf basil on through the active growing season, whenever roots fill the current container — there is no single date, just "before it becomes root-bound". Avoid potting on during a cold snap.

Step-by-step: repotting lettuce leaf basil

Pot on before it is root-bound. Check lettuce leaf basil regularly; move it up as soon as roots reach the edge of the cell or pot, not after they have circled.
Step up one or two sizes. Choose the next container up — not a giant one. Cold, wet, unused soil around a small root system stalls seedlings.
Knock it out gently. Support the stem, tip the pot, and ease the rootball out without breaking it. A little teasing of circled roots at the base is fine.
Pot into rich mix. Set it into fresh rich, moisture-retentive, well-drained loam or quality potting mix at the same depth (tomatoes are the exception — they can go deeper to root along the stem).
Water in and grow on. Water well, keep it in good light, and resume feeding once it is established and growing again.

Aftercare

Water lettuce leaf basil in well and keep it in bright light; a freshly potted-on seedling can wilt for a day while roots settle, so do not overcompensate by drowning it. Do not fertilise for about 1 week — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for lettuce leaf basil

Lettuce Leaf Basil wants rich, moisture-retentive, well-drained loam or quality potting mix. Wants fertile soil packed with organic matter and free drainage; pH 6.0-7.0. The big leaves are a sign of a heavy feeder, so a compost-enriched bed or container mix pays off. Avoid cold, soggy soil that rots the stems. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting lettuce leaf basil — frequently asked questions

How often should you repot lettuce leaf basil?

Pot on seedlings as they grow; not a perennial repot for lettuce leaf basil. Lettuce Leaf Basil is a seasonal crop, so you pot it on as a growing plant rather than repotting a perennial. Step seedlings up gradually into rich, moisture-retentive, well-drained loam or quality potting mix so the roots never circle the cell, ending in a large final container. A root-bound transplant stalls and never fully recovers.

What size pot does lettuce leaf basil need?

When is the best time of year to repot lettuce leaf basil?

Can you put lettuce leaf basil straight into a much bigger pot?

No. Even a fast-growing lettuce leaf basil should only go up one pot size at a time. A vastly oversized pot holds a reservoir of wet soil the roots cannot reach, which stays cold and soggy and rots the roots — the opposite of what you wanted.

Should you fertilise lettuce leaf basil after repotting?

Not immediately. Wait about 1 week after repotting lettuce leaf basil. Fresh mix already contains nutrients, and feeding freshly cut or disturbed roots burns them. Resume your normal feeding routine once you see new growth.