Operation Overview
Current Program Audit
Primary Species
Firebush, coontie, beautyberry, wild coffee, sabal palm, live oak (3-gal through 25-gal), longleaf pine seedlings
Container Types
1-gal annuals/perennials, 3-gal shrubs, 7-gal and 25-gal trees; propagation flat seedlings
Current Fertilizer Program
Osmocote Plus 15-9-12 controlled-release applied at potting — 1 tsp/gal container volume. Supplemented with Peters Professional 20-20-20 water-soluble at 200 ppm N weekly during active growing season. Fungicide rotation: Subdue Maxx (metalaxyl) every 21 days for Phytophthora control, Daconil alternating for foliar fungal.
Current Inoculant Program
MycoApply Endo Maxx applied at transplant — AMF species only (Glomus intraradices, G. mosseae, G. aggregatum, G. etunicatum). Applied to all container types including live oak and longleaf pine. Note: this product forms no association with ectomycorrhizal species — see Section 3 for species-specific breakdown.
Phosphorus Audit
P Levels by Container Type
Critical Finding
Mycorrhizal colonization is blocked when available phosphorus exceeds 50 ppm in the rooting zone. Every container type tested exceeded this threshold. AMF inoculants applied at current P levels are forming zero association with plant roots. The inoculant cost is a complete waste until P is corrected.
| Container Type | Available P (ppm) | Threshold for Colonization | Status |
|---|---|---|---|
| 1-gal shrubs (potting mix + Osmocote) | 172 ppm | <50 ppm | Blocked |
| 3-gal shrubs (established containers) | 148 ppm | <50 ppm | Blocked |
| 7-gal trees (live oak, sabal palm) | 163 ppm | <50 ppm | Blocked |
| Propagation flat seedlings | 94 ppm | <50 ppm | Blocked |
| Irrigation water (source) | 8 ppm | <15 ppm preferred | Acceptable |
Immediate action required before inoculation: All new potting mixes must transition to a low-P fertilizer specification. See Phase 1 protocol for transition product and rate. Existing containers at high P levels will slowly deplete P through plant uptake — new containers entering the protocol should be set up correctly from day one.
Biology Baseline
What's in Your Containers
Samples taken from 3-gal container media (shrubs) and propagation flat soil. Analyzed under compound microscope using Soil Food Web methodology.
| Organism | Reading | Target (Container) | Status | Note |
|---|---|---|---|---|
| Total Bacteria | 24 µg/g | 100–300 µg/g | Low | Adequate for basic cycling; target 4× improvement |
| Total Fungi | 1.2 µg/g | 50–150 µg/g | Critical | Fungicide rotation has eliminated most beneficial fungi |
| AMF Colonization (root section) | 0% | 25–60% | Blocked by P | No colonization despite inoculant application |
| Phytophthora signatures | Present — low-moderate | Absent | Detected | Oospores visible in container bed samples |
| Trichoderma (biocontrol) | Absent | Present | Absent | Eliminated by Subdue Maxx applications |
| Bacillus spp. | Trace | Active populations | Suppressed | Partially resistant to metalaxyl — some survival |
| Protozoa (flagellates) | Sparse | Active cycling populations | Low | Nutrient cycling suppressed — nutrient lockup risk |
Root cause summary: The fungicide rotation (Subdue Maxx / Daconil) has created a biology vacuum — Trichoderma and Bacillus, which are your natural Phytophthora suppressors, are absent. With no competition, Phytophthora persists indefinitely regardless of fungicide applications. Fungicide resistance builds while the biology that would replace it is prevented from establishing. This is a self-reinforcing cycle that requires breaking at the fungicide stage, not the Phytophthora stage.
Inoculation Map
Species-Specific Inoculant Assignment
Important: Live oak and longleaf pine are ectomycorrhizal. Applying AMF inoculants to these species forms no mycorrhizal association — the species are biologically incompatible. Every live oak and pine at this nursery is currently receiving an inoculant with zero effect. This changes immediately in Phase 1.
| Species | Mycorrhizal Type | Correct Inoculant | Application Method | Current Program |
|---|---|---|---|---|
| Firebush, beautyberry, coontie, wild coffee | AMF | Glomus intraradices / G. mosseae | Root zone powder at transplant — after P corrected | AMF applied — ineffective at current P levels |
| Sabal palm, thatch palm | AMF | Glomus intraradices, Rhizophagus irregularis | Root ball drench at transplant | AMF applied — ineffective at current P levels |
| Fishtail palm, queen palm | AMF | Glomus mosseae + G. etunicatum mix | Root zone powder at transplant | AMF applied — ineffective at current P levels |
| Live oak (Quercus virginiana), sand live oak | Ectomycorrhizal | Pisolithus tinctorius + Cenococcum geophilum | Root dip or drench at seedling/transplant stage | AMF applied — zero effect on oaks |
| Longleaf pine, slash pine seedlings | Ectomycorrhizal | Pisolithus tinctorius (primary) | Root zone incorporation at transplant | AMF applied — zero effect on pines |
Phase 0
Stop List — Before Inoculation Begins
Osmocote Plus 15-9-12 — Discontinue for New Mixes
Osmocote Plus drives media P to 148–172 ppm within weeks of potting — well above the 50 ppm colonization threshold. All new container mixes should transition to the low-P fertilizer specified in Phase 1. Existing containers with Osmocote already applied will cycle through — do not add additional Osmocote while biology program is ramping up. Existing containers can still receive biocontrol treatments.
Subdue Maxx (Metalaxyl) — Discontinue
Metalaxyl eliminates Trichoderma from treated media. Since Trichoderma is your primary Phytophthora biocontrol organism, every Subdue Maxx application clears the field for Phytophthora to re-establish. Stopping Subdue Maxx allows Trichoderma populations (reintroduced in Phase 1) to establish and begin natural suppression. The transition period — 3–4 weeks without Subdue Maxx — requires diligent watering management (wet-dry cycles, not continuous moisture) to prevent Phytophthora pressure during the biocontrol establishment window.
Peters Professional 20-20-20 — Reduce P Fraction
The 20-P in Peters 20-20-20 is unnecessary for established container production and adds to the P accumulation blocking colonization. Switch to Peters Professional 20-10-20 or equivalent at the same application frequency. This alone drops the supplemental P load by 50%.
Phase 1
Inoculation & Biocontrol — Weeks 1–12
Biocontrol Foundation — Trichoderma + Bacillus
Week 1–2 · Before any inoculant application
Product
TCC Aerated Liquid Extract (Bacillus-dominant brew)
Rate
1 gal per 100 sq ft bench area, diluted 1:4
Method
Overhead drench to containers; apply at watering time — morning preferred
Product
Trichoderma harzianum (RootShield or equivalent)
Rate
Per label for drench application
Method
Applied separately from extract — at least 48 hours later; water in immediately
AMF Inoculation — Ornamentals, Palms, Native Shrubs
Week 4 · After first biocontrol application; after P program adjusted
Product
Glomus intraradices / G. mosseae powder inoculant
Rate
Per label — 1 tsp at root contact zone per transplant
Method
Applied as powder to root zone at transplant or pot-up; do not mix with fertilizer
Ectomycorrhizal Inoculation — Live Oak, Pines
Week 4 · Same timing as AMF for other species
Product
Pisolithus tinctorius (Mykos Xtreme or Planet Natural ecto product)
Rate
Powder: ½ tsp per seedling; gel drench: per label for gallon containers
Method
Root dip for seedlings; root zone powder at transplant for gallon containers; water in same day
Note
Do NOT apply AMF inoculant to these species — it has no effect and wastes product
Phase 3 Deliverable
Custom Container Media Recipe
Target: a production-ready media mix that supports biology from day one — P below 50 ppm, bacterial diversity built in, biochar providing permanent microbial habitat. This recipe is the end-state goal for new container production.
Magnolia Green Native Nursery — Phase 3 Container Media
Florida pine bark fines (3/8" and smaller) — base
60% by volume
Perlite — drainage and aeration
15% by volume
TCC Worm Castings — biology and nutrition
15% by volume
TCC Charged Biochar — microbial habitat
10% by volume
Fertilizer: Nutricote 13-2-5 — low-P spec (do not substitute Osmocote Bloom 3-11-11; 11% P will block colonization)
½ tsp / gal container volume
Inoculant: applied at transplant per species map above
At transplant, not in media mix
P note: At the above ratios, available P in finished media targets 22–35 ppm — well below the 50 ppm colonization threshold. Worm castings contribute trace P that is complexed with organic matter and not immediately plant-available, maintaining low free P while building biology.
End Goals
What a Fully Transitioned Operation Looks Like
| Metric | Current | 6-Month Target | Phase 3 End Goal |
|---|---|---|---|
| Available P in new media | 148–172 ppm | <80 ppm (new containers) | <50 ppm — colonization window open |
| AMF colonization rate (root section) | 0% | 15–25% (new P-corrected containers) | 30–50% in active containers |
| Phytophthora detection | Low-moderate presence | Reduced — Trichoderma establishing | Below detection threshold in routine samples |
| Trichoderma presence | Absent | Present in treated containers | Self-sustaining in properly managed media |
| Post-sale transplant survival (90-day) | Unknown — not tracked | Tracking established; baseline set | Documented improvement over baseline |
| Fungicide applications | Every 21 days | Every 60 days (transitional) | As-needed only — Phytophthora managed biologically |