garden-fertilizer

name: garden-fertilizer description: "Build science-based organic fertilizer recipes from purchasable ingredients for any garden type. Use this skill whenever the user mentions fertilizer, soil amendments, plant feeding, NPK, compost tea, garden nutrition, soil building, raised bed soil mix, or seasonal feeding schedules — even if they don't say 'fertilizer' explicitly. If they're talking about what to feed their plants, why leaves are yellowing, or how to prep a bed for spring, this skill applies."

Garden Fertilizer Recipe Builder

Build custom organic fertilizer blends from ingredients available on Amazon or at local garden centers. Recipes are grounded in soil science — nutrient ratios, release rates, pH interactions, and cost-effectiveness all factor in.

How This Skill Works

When a user asks for a fertilizer recipe, you walk through a structured process: understand what they're growing, where, and in what conditions — then build a recipe that delivers the right nutrients at the right time for the right price.

Step 1: Gather Context

Ask the user for the essentials. You don't need all of these — work with what they give you and fill gaps with sensible defaults.

What you need:

• What they're growing — specific plants, or "general vegetable garden," etc.
• Growing method — raised bed, in-ground, container, straw bale, hydroponic. Default to raised bed if unspecified.
• USDA zone — for seasonal timing. If they don't know, ask for their city/state.
• Soil situation — new build, existing bed being amended, soil test results if available.
• Goals — maximum yield, low maintenance, budget-conscious, building long-term soil health, fixing a specific deficiency.

If they don't have a soil test, that's fine — most home gardeners don't. Work from general guidelines for their plant type and note where a soil test would remove guesswork.

Step 2: Build the Recipe

Read references/ingredients.md for the full ingredient database — NPK values, release rates, costs, and interaction notes.

Read references/plant-profiles.md for target nutrient ranges by plant type.

Recipe Design Principles

Match nutrients to plant needs. Every plant has an ideal N-P-K range and specific micronutrient requirements. A tomato heavy-feeder mix is very different from a leafy greens blend. Consult plant-profiles.md for the targets, then select ingredients from ingredients.md to hit those numbers.

Layer release rates. A good organic fertilizer blend includes:

• Fast release (available within 1-2 weeks): fish emulsion, blood meal, liquid kelp
• Medium release (1-4 months): fish meal, alfalfa meal, feather meal
• Slow release (3-12 months): bone meal, rock phosphate, greensand, kelp meal

This layering means the plant gets immediate nutrition at transplant/emergence and sustained feeding throughout the season without burning or feast-famine cycles.

Respect nutrient interactions. Some combinations work synergistically, others compete:

• Calcium and magnesium compete for uptake — don't overload both
• Phosphorus availability drops sharply outside pH 6.0-7.0
• High nitrogen suppresses fruiting; excess in flowering stage hurts yield
• Sulfur lowers pH; lime raises it — these are tools, not just nutrients
• Mycorrhizal fungi are destroyed by high phosphorus — go easy on bone meal if inoculating

Keep it cost-effective. Growing food should save money, not cost more than the grocery store. Prioritize ingredients that deliver the most nutrition per dollar. See the cost-effectiveness notes in ingredients.md. Where two ingredients serve the same purpose, recommend the cheaper one unless there's a scientific reason for the pricier option.

Recipe Output Format

Present every recipe with these sections:

1. Recipe Summary

• Name/purpose of the blend
• Target plants
• Growing method
• Expected coverage (e.g., "enough for a 4x8 raised bed")

2. Ingredient List (Shopping List) For each ingredient:

• Product name (with common Amazon search term)
• Amount needed for the recipe
• Approximate cost
• What it contributes (N-P-K and any key micronutrients)

3. Nutrient Breakdown A table showing:

Show whether the blend hits, exceeds, or falls short of the target range.

4. Mixing Instructions

• How to combine the dry ingredients
• Storage notes (most dry blends keep 6+ months in a sealed container)
• Application method — top dress, mix into soil, side dress, etc.
• Rate per square foot or per plant

5. Seasonal Maintenance Calendar Read references/seasonal-guide.md for zone-specific timing.

A month-by-month (or phase-by-phase) schedule showing:

• When to apply the base mix
• When and what to use for mid-season feeding (fish emulsion, compost tea, liquid kelp, etc.)
• When to back off nitrogen (especially for fruiting crops approaching harvest)
• Fall/winter soil building if applicable

6. Total Estimated Cost

• Per-batch cost
• Cost per square foot or per plant
• Note which ingredients they might already have or can source free (e.g., wood ash, homemade compost)

Step 3: Explain the Science

Don't just hand them a recipe — help them understand why. Briefly explain:

• Why you chose these specific ingredients over alternatives
• How the different release rates work together over the season
• Any nutrient interactions they should be aware of
• What signs to watch for that indicate the plant needs adjustment (yellowing leaves = nitrogen, purple stems = phosphorus, leaf edge browning = potassium, blossom end rot = calcium)

Keep explanations accessible — no jargon without definition. The user is a gardener, not a soil chemist.

Common Scenarios

"I'm building a new raised bed"

This is a soil-building scenario, not just fertilization. Recommend a base soil mix (e.g., 1/3 compost, 1/3 peat or coco coir, 1/3 vermiculite/perlite) PLUS the fertilizer blend mixed in. The first-year bed needs more amendment than an established bed.

"My tomatoes aren't producing"

Diagnose before prescribing. Too much nitrogen pushes leaf growth over fruit. Ask about current feeding, foliage appearance, and flowering. The fix might be less nitrogen and more phosphorus/potassium, not more fertilizer.

"What should I add in the middle of the season?"

Mid-season feeding is mostly about fast-release sources: fish emulsion (5-1-1) every 2-3 weeks, liquid kelp for micronutrients and growth hormones, compost tea for microbial activity. The base dry mix handles the slow background nutrition.

"I want to do this as cheaply as possible"

Focus on: homemade compost (free), bulk purchases of the 3-4 most impactful amendments, and avoiding boutique products with high markups. A simple blood meal + bone meal + kelp meal + greensand blend covers most needs for under $30 and lasts a full season for a typical raised bed.

Important Caveats

• Organic fertilizers depend on soil biology to break down. Cold soil (<50°F) dramatically slows nutrient release. Account for this in early-season recommendations.
• pH matters enormously. Most vegetables thrive at 6.0-7.0. If pH is off, nutrients become unavailable regardless of how much fertilizer is applied. Always mention pH.
• More is not better. Over-fertilization causes salt buildup, nutrient lockout, and can kill beneficial soil microbes. Recommend conservative rates and let the gardener increase based on plant response.
• These are guidelines, not prescriptions. Soil is a living system with enormous variation. Encourage observation and adjustment over rigid adherence to a formula.