Trichoderma Harzianum

Regular price $12.00

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Trichoderma Harzianum

At A Glance

Trichoderma harzianum Rifai strain T-22 is not just a soil additive; it is a high-performance biological fungicide and root enhancer. While predatory mites guard your leaves, T-22 guards your root zone. This specific strain was hybridized to thrive across the widest possible range of soil types and temperatures, creating a living "shield" around plant roots that blocks pathogens and unlocks trapped nutrients.

Field Notes — Trichoderma T-22

Organism Trichoderma afroharzianum strain T-22 (formerly classified as T. harzianum, strain KRL-AG2)
Type Beneficial soil fungus — root colonizer
Sold by Weight 
Formulation Wettable powder
Ships as Viable spores
Applied as Soil drench, or incorporated dry into mix at potting
Where it lives Root surface — colonizes and grows outward with the root system
Mode of action Occupies root space ahead of pathogens, competes for nutrients and exudates, parasitizes pathogenic fungi directly, and triggers the plant's own defense response
Works against Pythium, Rhizoctonia, Fusarium, Thielaviopsis, Cylindrocladium — root and crown rot organisms
Doesn't work against Foliar disease (powdery mildew, leaf spot), bacterial rot, insects, fungus gnats
Timing Preventive. Establishes at potting, propagation, or deflasking — before a pathogen has the root surface
Soil temp Active 50–90°F; colonizes fastest 60–85°F
Moisture Moist soil required for establishment; will not colonize dry media
Persistence Colonizes for the life of the root system if undisturbed; reapply after repotting or heavy media change
Mix water Dechlorinated. Chlorine and chloramine reduce spore viability
Mixed slurry Apply the same day. Spores don't hold in solution
Refrigerate Yes — refrigeration extends viable shelf life (verify against your supplier's label)
Compatible with Mycorrhizae, beneficial nematodes, predatory mites, beneficial insects, springtails, most insecticides
Keep separate from Systemic and broad-spectrum fungicides — chemical fungicides will kill it. Check the interval on the fungicide label before applying
Safe around Pets, children, plants at any stage
Handling Avoid inhaling dust when measuring dry product — mask advisable, standard for any powdered fungal product
Target Pathogens

T-22 is an aggressive beneficial fungus that out-competes "bad" fungi for space and resources.

  • Pythium & Phytophthora: The leading causes of damping-off and root rot.
  • Fusarium & Rhizoctonia: Soil-borne diseases that cause wilting and stem rot.
  • Sclerotinia: Targets a wide range of vegetables and ornamentals.
  • Secondary Benefit: Induces systemic resistance, making the plant naturally more resilient to foliage-based stresses.
Environmental Needs

Trichoderma harzianum T-22 is an adaptable strain, engineered to colonize roots across a wider range of conditions than most biological fungicides. However, a few environmental factors determine how quickly and aggressively it establishes.

  • Temperature: Active between 50°F – 95°F (10°C – 35°C). Peak colonization occurs between 65°F – 85°F — the same range most tropical houseplants and indoor grows prefer.
  • Moisture: T-22 spores require moisture to germinate and begin root colonization. Apply as a drench to a moist (not waterlogged) medium. Bone-dry soil delays activation.
  • pH: Performs best in a pH range of 5.5 – 7.0. Compatible with most soil, coco coir, and perlite mixes used in tropical plant cultivation.
  • Light Sensitivity: Do not apply T-22 in direct, intense light. UV exposure can degrade spore viability. Water in during early morning or evening, or under grow lights rather than direct sun.
  • Compatibility: T-22 is not harmed by beneficial nematodes or predatory soil mites. Avoid applying alongside broad-spectrum fungicides, which will kill the colony.
Selection Guide

Trichoderma T-22 is a foundational "preventative shield." It is most effective in these specific growing environments:

  • The Tissue Culture (TC) Transition: TC plants are raised in sterile environments and lack a natural immune system. Applying T-22 during the acclimation or "hardening-off" phase provides immediate biological protection when they are most vulnerable to damping-off.
  • The Hydroponic & Sterile Medium Guard: In Coco Coir, Rockwool, or Perlite, your medium is a "blank slate." Using T-22 ensures the "good guys" occupy the root zone first, leaving no room for pathogens to establish.
  • The High-Stress Transplant: Every time you up-pot, roots suffer microscopic tears. A T-22 drench during transplanting "plugs" these entries and stimulates faster root recovery.
  • The Mother Plant Insurance: For plants that stay in the same pot for long periods, T-22 boosters keep the rhizosphere healthy and active, ensuring your clones are taken from a vigorous, disease-free parent.
How to Use

Trichoderma T-22 is a concentrated wettable powder. Because the spores are living organisms, they do not "dissolve" like sugar—they stay suspended in the water. To prevent clumping and ensure the spores actually reach your roots, follow this simple process:

1. Measure Your Dose
Choose the rate that matches your plant's stage:

  • Tissue Culture (TC) & Cuttings: 0.5 teaspoons per gallon (0.5g per Litre).
  • Established Plants: 1 teaspoon per gallon (1g per Litre).
  • Mother Plants & High-Stress Areas: 1.5 teaspoons per gallon (1.5g per Litre).

2. Create Your Concentrated Slurry

  • Place your measured dose into a small container (like a measuring cup or jar) with just one cup of room-temperature water.
  • Whisk or stir vigorously for 30 seconds until it forms a smooth, uniform liquid.
  • Why? This "pre-mix" breaks up dry clumps. If you dump dry powder into a large tank, it will float on top and fail to colonize your roots.

3. Dilute & Apply

  • Pour your concentrated slurry into your final volume of water (watering can, bucket, or reservoir) and stir.
  • Drench the Roots: Pour the mixture directly at the base of the plant until the root ball is saturated.
  • Keep it Moving: If you are watering many plants, give the bucket a quick stir every few minutes. The spores are heavy and will naturally settle at the bottom if left still.
How They're Shipped

Unlike predatory mites, which are active insects, Trichoderma T-22 is shipped in a dormant spore state. This makes it much more resilient during transit, but proper storage is still the key to its long-term potency.

  • Transit Durability: T-22 spores are shelf-stable at room temperature during shipping. Short exposure to standard transit temperatures will not "kill" the product. However, we recommend retrieving your package promptly to avoid prolonged exposure to extreme heat (over 100°F).
  • Immediate Care: Upon arrival, store the sealed pouch in a cool, dry, and dark place. A kitchen cupboard or climate-controlled grow room is perfect for short-term use.
  • Long-Term Storage: If you do not plan to use the entire package within 6 months, we recommend refrigeration (35°F–45°F). This keeps the spores in a deep dormancy and can extend their viability for up to 18 months.
  • Do Not Freeze: Freezing can damage the cellular structure of the spores. Always keep the product above 32°F.
  • Keep Sealed: Humidity is the enemy of dormant spores. Keep the pouch tightly sealed when not in use to prevent moisture from "activating" the spores inside the bag.

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FAQ

What is your Live Delivery Guarantee?

We guarantee that our Trichoderma T-22 arrives with a 100% viable spore count. Because you cannot see these organisms with the naked eye, our guarantee for this product is handled differently than our predatory mite or nematode guarantees.

  • Viability Guarantee: We ensure that the product has been stored in climate-controlled conditions and shipped in UV-protected packaging to maintain peak potency. We guarantee the spores are "active" and ready to colonize your roots the moment they are hydrated.
  • The "Proof of Life" Period: Unlike mites (which you check on day one), the proof of Trichoderma is seen in the plant's response. We offer a 21-day viability window. If you apply the product as directed and do not see an improvement in root health (whiter roots, increased root mass) or plant vigor within three weeks, contact us.
  • Shipping Protection: If your package arrives punctured, wet, or has been exposed to extreme heat (left in a mailbox over 100°F) and the powder is clumped or discolored, take a photo and contact us within 24 hours. We will replace the product to ensure you are starting with a healthy colony.
Is T-22 a fertilizer?

No, it is a beneficial fungus. However, it makes your fertilizer work better by "solubilizing" nutrients—breaking down minerals that are normally trapped in the soil so the plant can easily drink them up.

Can I use T-22 if I already have Root Rot?

T-22 is most effective as a preventative. If your plants are already dying from advanced root rot, T-22 may struggle to catch up. For best results, apply to healthy plants or at the very first sign of stress.

How often should I apply it?

A single application at planting can last for months, but for high-intensity indoor grows, we recommend a "booster" drench every 4–6 weeks to ensure the root zone remains fully colonized.

Will it harm my Beneficial Nematodes or Soil Mites?

Not at all. Trichoderma is a fungus that targets other fungi; it does not harm beneficial insects or microscopic worms. In fact, they often work together to create a healthier soil ecosystem.

I see white fuzz on my soil after using T-22. Is that bad?

Usually, no! That is often the Trichoderma colony growing on the soil surface. Unlike gray mold or damping-off, this "good" fuzz is protecting your plant.

How does T-22 help with acclimating Tissue Culture (TC) plantlets?

Tissue Culture plantlets are raised in a sterile, 100% humidity environment and lack the "microbial memory" needed to survive in the real world. When you move them into soil or coco, they are entering a biological vacuum. T-22 acts as an immediate "bodyguard," colonizing the roots before harmful pathogens can. It also helps the plantlet develop its waxy cuticle and root structure faster, significantly reducing "transplant shock" and the high mortality rates often seen during the hardening-off phase.

Help! I'm overwhelmed

Yeah, it's a lot the first time you're using predatory mites. Please email us at info@fgmnnursery.com and we'll be happy to help!

  • 5 stars: 6 (75%)
  • 4 stars: 2 (25%)
  • 3 stars: 0 (0%)
  • 2 stars: 0 (0%)
  • 1 star: 0 (0%)
A
Anonymous
Good product

Good product, fast delivery! Thank you!

A
Anna

Hard to measure out how much you need, but otherwise, ive really enjoied everything ive purchased from this shop.

D
Dysia
My Positive Experience with Trichoderma

After reading many articles, I decided to order Trichoderma. I used it according to the instructions, and so far my plants are in very good condition. I reduced fertilizing because after applying it, the plants do not show any nutrient deficiencies. I think it was a good decision because at this time last year my plants were already getting sick. The ordering process itself was trouble-free, and I waited about a week for the delivery, but it was worth it.

L
Luci W.
This is magical

This is magical. I love it

W
Wade B.
Ordering and delivery were flawless

Ordering and delivery were flawless. Instructions for use and storage were good and helpful

Q
Quoi N.
It’sgood

It’sgood

D
Daniel T.
First-time user: would recommend

It's my first time using Trichoderma solution as a bio-fungal agent to prevent damping off. This stuff is great. I've already had success using it as a pre-soak and soil drench to germinate adeniums, aloes, and boswellia, and I've also drenched the soil of my other native plant starts. I've had zero issues with mold growth or damping off so far.

Z
Zvezdelin T.
I love it! Good product! Thanks!

I love it! Good product! Thank you!

M
Mel

Does this help with black rot on grape vines

FGMN Nursery

Hi!

Unfortunately, no. That’s more of a foliar disease.

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