Lettuce Container Soil Mix

Lactuca sativa

Shallow-rooted cool-season green that thrives in a moisture-retentive, vermicompost-rich mix.

Container:
2 gal / 30 cm wide planter
pH:
6–6.8
EC:
0.8–1.2 mS/cm
Sun:
4–6 hr
Light:
Part sun; appreciates afternoon shade in summer

Components

Percentages by volume. Quantities scaled for a 2-gallon container (US units).

Component % Amount
Quality potting mix
Base structure, initial nutrients
45% 3.5 qt
Coco coir (low-EC, buffered)
CEC, moisture buffering
25% 2 qt
Vermicompost / Worm castings
Nutrients, microbes, growth hormones
20% 1.5 qt
Perlite
Drainage, aeration
10% 3.25 cup

Per-container amendments

Scaled linearly to your container size. Apply at transplant or as side-dress per the notes on each line.

Growing notes

- Target ideal temps: nights ~50 F, days up to 68 F — bolts hard above 80 F. - Keep evenly moist; container compost dries quickly and dry spells trigger bolting. - Sow successively every 2 weeks until temps hit 80 F, then resume mid-August for a fall crop. - Harvest individual outer leaves at baby stage for multiple cuts, or shear whole head at soil. - In a 2 gal pot, fortnightly liquid organic feed keeps growth tender. - Use a peat-free, moisture-retentive base; loose-leaf cultivars are most forgiving.

Want to scale this to a different container size, save it to a plot plant, or track applied dates? Open it in the interactive calculator.

References

  1. Growing lettuce, endive and radicchio in home gardens — University of Minnesota Extension . University of Minnesota Extension
  2. How to grow lettuces — Royal Horticultural Society . RHS