About

Precision in agriculture determines the difference between a bumper crop and a failed harvest. This application utilizes Phenological Modeling to align biological lifecycles with local climatic constraints. By anchoring calculations to your specific Last Frost Date (LFD), the tool generates a synchronized timeline for over 60 crop varieties, optimizing for solar radiation, soil temperature, and risk mitigation.

Unlike static almanacs, this system accounts for critical variables: Vernalization Requirements, Photoperiod Sensitivity, and Thermal Comfort Zones. The interface provides a dynamic Gantt visualization, allowing growers to identify Succession Planting opportunities and manage spatial rotation efficiently. Whether you are practicing high-density market gardening or subsistence permaculture, accuracy in timing is the primary lever for maximizing biomass accumulation.

Formulas

The core logic utilizes thermal time models. The planting date P is a function of the probabilistic Last Frost Date (LFD) and the crop-specific physiological offset Δt.

P_indoor = LFD − Δt_maturity

For direct seeding, soil temperature T_soil is the limiting factor. The algorithm estimates the safe date D_safe based on historical thermal accumulation:

D_safe =

{

LFD − 4 weeks if HardyLFD + 2 weeks if Tender

Growing Degree Days (GDD) drive the harvest estimate, calculated daily as:

GDD = T_max + T_min2 − T_base

Reference Data

Family	Crop	Soil pH (pH)	Germination (°C)	Bio-Intensive Spacing (cm)
Solanaceae	Tomato (Indeterminate)	6.0−6.8	24−29	45−60
Solanaceae	Pepper (Bell/Hot)	6.0−6.5	26−32	30−45
Brassicaceae	Broccoli (Calabrese)	6.0−7.0	7−29	30−45
Brassicaceae	Kale (Lacinato)	6.0−7.5	10−30	20−30
Fabaceae	Bush Bean	6.0−7.0	16−30	10−15
Fabaceae	Pea (Snow/Snap)	6.0−7.5	4−24	5−8
Cucurbitaceae	Cucumber	5.5−7.0	21−35	30−40
Cucurbitaceae	Winter Squash	5.5−7.0	21−35	60−90
Apiaceae	Carrot	6.0−6.8	7−30	5−8
Asteraceae	Lettuce (Leaf)	6.0−7.0	4−27	15−20
Amaryllidaceae	Onion (Bulbing)	6.0−7.0	10−30	10−15
Chenopodiaceae	Spinach	6.5−7.5	2−24	10−15

Frequently Asked Questions

For "Tender" crops (Solanaceae, Cucurbitaceae), tissue damage occurs at 0°C (32°F). Ice crystals rupture cell walls, leading to immediate necrosis. However, "Hardy" crops (Brassicas, Alliums) utilize cryoprotectant sugars in their cells, allowing them to withstand temperatures down to -5°C (23°F) depending on acclimation.

A False Spring is a period of warmth followed by a hard freeze. To mitigate this, do not rely solely on air temperature. Monitor soil temperature. If you must plant early, use passive solar gain tools like cloches, row covers, or cold frames which can provide a +2°C to +4°C thermal buffer.

Root vegetables (Carrots, Parsnips) have taproots that suffer "Transplant Shock" if disturbed, leading to forked or stunted growth; they must be direct sown. Crops with long maturity cycles (Tomatoes, Peppers) require a head start indoors because the temperate growing season is insufficient for them to reach fruit maturity from seed.

This is the practice of seeding crops at timed intervals (e.g., every 14 days) rather than all at once. This ensures a continuous harvest window rather than a glut of produce followed by scarcity. Fast-maturing crops like Radishes and Lettuce are ideal candidates for this method.

Currently, this algorithm is calibrated for the Vernal (Spring) season, anchoring to the Last Frost Date. Fall gardening requires anchoring to the First Autumn Frost and calculating backward. While some dates overlap, photoperiod degradation in autumn significantly slows growth rates compared to spring.