The right amount of nitrogen, exactly when the crop can use it.
A short-cycle organic program for baby lettuce, spinach, and spring mix: a Phyta-Grow® Leafy Green Special pre-plant base and two quick, plant-available Phytamin® Jumpstart applications — sized to match crop demand, not exceed it.
Baby greens are a fast crop that punishes over-fertilizing.
Baby leafy greens are harvested in 20–60 days at high planting density, and they take up only a modest amount of nitrogen — UC and CDFA FREP research measured roughly 65–85 lb N/acre in a single short cycle. FREP trials found that common grower practices apply far more nitrogen than the crop removes, leaving high residual nitrate in the soil after harvest. The goal of this program is the opposite: supply well-timed, plant-available nitrogen that matches demand, so you can apply less and leave less behind.
One dry base, two quick liquid feeds.
| Timing | Product | Rate | N supplied |
|---|---|---|---|
| Pre-plant Incorporate top 2–3″ | Phyta-Grow® Leafy Green Special 7-1-2 Dry, all plant materials | 500–800 lb/acre | 35–56 lb N/acre |
| 15–20 days Post-germination | Phytamin® Jumpstart 4-1-1 Overhead irrigation | 10–20 gal/acre | ~3.6–7.1 lb N/acre |
| 10 days Before harvest | Phytamin® Jumpstart 4-1-1 Overhead irrigation | 10–20 gal/acre | ~3.6–7.1 lb N/acre |
| Program nitrogen from COFI products | ~42–70 lb N/acre | ||
Incorporate top 2–3″
Dry, all plant materials
Post-germination
Overhead irrigation
Before harvest
Overhead irrigation
Why a final feed 10 days before harvest works.
Phytamin® Jumpstart delivers nitrogen as ammoniacal N, so it skips the slow mineralization that protein-based dry fertilizers require. Under suitable soil conditions, its nitrogen nitrifies — converts from ammonium to plant-available nitrate — at over 90% within about 10 days.¹ That means a final application 10 days before harvest delivers nearly its full nitrogen value to the crop, right at the label’s minimum pre-harvest interval.
¹ Nitrification rate: California Organic Fertilizers internal data (ammonium-to-nitrate conversion >90% within ~10 days under suitable soil conditions).
Placed across a short cycle.
500–800 lb
10–20 gal
10–20 gal
The pre-plant Phyta-Grow® Leafy Green Special base feeds early growth as the stand establishes. The two Phytamin® Jumpstart applications supply immediately available nitrogen mid-cycle and again just before harvest — carrying the crop to size without loading the soil with nitrate the plants can’t use in time.
Crop N uptake and cycle length: CDFA FREP & UC Davis California Crop Fertilization Guidelines (Lettuce / Leafy Greens); Smith et al., high-density baby leafy greens N uptake (~65–85 lb N/acre per cycle). Residual-nitrate and over-application findings: CDFA FREP baby leafy greens research updates (Sanchez / Montazar). Seedling-safety threshold: UC / Imperial Valley lettuce guidelines. Nitrification rate: California Organic Fertilizers internal data. Product rates and densities: Phytamin® and Phyta-Grow® CDFA-registered labels.
THE ORGANIC AGRONOMIST
Growing Organic Baby Leafy Greens: Why Timing Matters More Than Total Fertility
Explore how well-timed nitrogen, uniform establishment, and careful irrigation help organic baby leafy greens make the most of a short growing season.
