Season Plan

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Season insights
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No insights yet—enter frost dates and crop details to generate analysis.


                

Add your frost dates and crop choice to build a sowing and harvest calendar.

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Introduction

A planting calendar turns seasonal timing into a workable schedule. Gardeners use it to decide when to start seed, when to move plants outside, when direct sowing is realistic, and whether harvest is likely to finish before autumn cold becomes a problem. This planner builds that schedule from frost dates, crop timing, and a few practical field-preparation settings.

The package asks for the average last spring frost, an optional first fall frost, a USDA zone, a crop preset or custom maturity profile, and the style of harvest you want. From there it lays out seed-starting, hardening, bed preparation, transplant or direct-sow dates, harvest timing, and any follow-up successions that still fit inside the modeled season.

That makes it useful when the same bed could be managed in very different ways. Tomatoes may need an indoor lead and a narrower late-season harvest window. Lettuce benefits from shorter gaps and quicker repetition. Bush beans and carrots often fit a direct-sow path with fewer indoor steps. The planner makes those differences visible before you commit labor and space.

The result is not just a date list. You get summary badges, a milestone table, a full planting schedule, insight notes, a timeline chart, and a JSON export. Those views are helpful when one person starts seed, another manages beds, and everyone needs the same calendar.

Treat the output as a planning model rather than a guarantee. USDA zones describe winter minimum-temperature bands, not annual vegetable planting dates by themselves, and average frost dates do not capture every yard, slope, tunnel, or sudden cold snap. Local notes still matter.

Everyday Use & Decision Guide

Begin with the two dates that matter most: your average last spring frost and, if you know it, your average first fall frost. Those anchors do more work than the zone selector. The zone adds context and a harvest-padding rule, but the entered frost dates drive the calendar itself.

Next choose a preset that is close to the crop you actually plan to grow. The shipped presets load days to maturity, transplant lead, default succession spacing, direct-sow preference, and a harvest-window length. If your packet or cultivar differs, switch to Custom and enter your own maturity and lead values instead of forcing a preset to do a job it was not built for.

The harvest goal shapes cadence rather than the biology of the crop. Fresh table tightens spacing to keep produce coming steadily, Preserving batch widens spacing to create a larger flush, and Succession harvest keeps the preset rhythm. If those defaults do not fit your workflow, the succession override lets you set a fixed day interval.

Which settings matter most in common situations
Situation Setting to watch first Why it matters
You want a steady kitchen harvest Harvest goal and Successions Those settings decide whether plantings are bunched together or spread through the season.
You expect to direct sow instead of transplant Direct sow Turning it on removes indoor seed-start and hardening phases and changes the early field-date logic.
You need prep tasks to show up before field dates Bed prep lead Adds explicit pre-plant bed work ahead of the main crop and each succession.
You want shareable notes that stay reproducible Notes seed Keeps the advisory note wording stable from one run to the next without changing any dates.

Technical Details

The package starts with required and optional date checks. Last spring frost must be a valid calendar date, and the first fall frost, when supplied, must come later. Numeric inputs are clamped locally: days to maturity to 25-180 days, transplant lead to 0-16 weeks, season extension to 0-6 weeks, hardening to 0-14 days, successions to 1-6 cycles, bed-prep lead to 0-21 days, and succession override to 0-60 days.

Crop presets carry the working assumptions that shape the schedule. Frost-sensitive crops start with a larger spring buffer than hardy ones. Direct-sow crops skip the indoor phases by default. Harvest windows differ by crop, so a tomato plan and a lettuce plan do not simply share the same maturity count with different labels.

Season extension affects both ends of the calendar. Early in the season it can shrink the spring waiting period before the main field date. Later in the season it can extend the harvest cap, but only within the package's fixed limit and only after subtracting a zone-based padding rule. That means extension helps, but it does not erase autumn risk.

Succession logic is rule-based. If you enter an override, the planner uses that fixed spacing with a minimum of 5 days. Without an override, it starts from the preset spacing, tightens it for Fresh table, widens it for Preserving batch, and otherwise keeps the base cadence. Requested successions that would fall after the modeled harvest end are dropped instead of being forced into the schedule.

Shipped crop presets
Preset Days to maturity Lead (weeks) Base gap (days) Direct sow default Harvest window
Tomato (indeterminate) 75 6 28 No 70 days
Pepper (sweet) 80 8 32 No 60 days
Lettuce (butterhead) 55 3 14 No 28 days
Bush bean 58 0 18 Yes 35 days
Kale 60 4 30 No 90 days
Carrot 70 0 21 Yes 45 days
Primary outputs and how to read them
Output What it represents
Season Milestones Main timing checkpoints such as seed start, hardening, field date, and harvest window.
Planting Schedule Chronological task list with phase, batch name, and notes for each step.
Planting Insights Short interpretation bullets based on season length, bed-prep lead, succession cadence, and risk notes.
Season Timeline Bar chart of indoor propagation, hardening, bed prep, growth, and harvest durations measured in days from the plan start.
JSON Structured dump of inputs, schedule items, metrics, summary badges, risk note, and zone context.

Date calculations and exports are generated in the browser session after the page assets load. The slug does not ship a dedicated server helper for the planning logic, so it behaves like a local planner with standard front-end asset loading rather than a hosted agronomy backend.

Step-by-Step Guide

  1. Enter the average last spring frost date for your location, then add the first fall frost date if you want the planner to cap the season against autumn risk.
  2. Choose the USDA zone that best matches your site so the summary note and harvest-padding rule reflect the climate band you are working in.
  3. Pick a crop preset or switch to Custom and enter your own days to maturity and transplant lead.
  4. Select the harvest goal, then decide whether the crop should stay on a transplant path or move to direct sow.
  5. Open the advanced controls for season extension, hardening days, successions, bed-prep lead, notes seed, and any fixed succession override.
  6. Read the summary badges first, then open the milestone table and schedule to make sure each task lands where you expect.
  7. Use the insights and timeline chart to spot tight buffers, trimmed successions, or an autumn overrun before you commit the plan to reminders.

If you are testing alternate strategies, keep the frost dates fixed and change only one operational setting at a time. That makes it obvious whether a shift came from crop choice, harvest goal, or season extension rather than from several changes layered together.

Interpreting Results

The summary badges are the quickest sense check. They tell you the planned field date, harvest window, succession count, season length when available, frost buffer when available, any bed-prep lead, the effective gap between successions, and the zone label. If those badges already look unrealistic, the deeper tabs will not rescue the plan.

The most important risk metric is the harvest buffer. A positive value means the modeled harvest ends before the first fall frost. Zero means harvest ends on the frost date itself. A negative value means the plan runs past the autumn cutoff and will need stronger protection, a faster cultivar, or a different planting strategy.

How to interpret the main metrics
Metric How to read it Common mistake
Season length Days between the entered spring and fall frost dates. Treating it as a guarantee for a specific year or microclimate.
Crop span Days from the main field date to the modeled harvest end. Assuming it covers every cultivar equally well.
Harvest buffer How far the harvest end lands before or after the first fall frost. Ignoring a negative value because the spring plan looked reasonable.
Succession count The number of plantings that still fit after the planner trims dates past the season cap. Assuming it will always equal the number originally requested.
Advisory note Readable planning guidance generated from the same schedule inputs. Reading it as a weather forecast or disease model.

The zone label is context, not a substitute for the dates you entered. USDA zone guidance is built from average annual extreme minimum temperatures, so it is useful for climate framing but not precise enough to replace local frost-history records for annual vegetable scheduling.

Worked Examples

  1. Default tomato plan in zone 6

    With the shipped defaults, the planner uses a last spring frost of 2025-04-20, a first fall frost of 2025-10-05, zone 6, the tomato preset, 2 weeks of season extension, and 3 successions.

    That produces a main transplant date of 2025-04-20, a seed-start date of 2025-03-02, hardening on 2025-04-13, a harvest window opening on 2025-07-04, and a modeled harvest end on 2025-09-12 with a 23-day autumn buffer.

  2. Direct-sown bush beans

    Switching to the bush bean preset and keeping direct sow on removes the indoor seed-start and hardening phases entirely.

    The resulting schedule becomes simpler: bed prep if requested, the sowing date, any later successions that still fit, and the harvest window. That is exactly what you want for crops that do not need indoor lead time.

  3. Preserving-focused calendar with custom spacing

    If you choose Preserving batch and set a fixed succession override, the planner stops using the preset rhythm and spaces field dates at your chosen interval instead.

    That is helpful when you want harvests to arrive in larger, more predictable waves for canning, freezing, or a market table, rather than in smaller continuous pickings.

FAQ

Does USDA zone replace local frost dates?

No. The zone gives climate context and drives the package's harvest-padding rule, but the actual calendar is built from the spring and fall frost dates you enter.

What happens if I leave the first fall frost blank?

The planner can still build the schedule, but the harvest window uses the default crop-based duration instead of an autumn cap tied to a fall frost date.

Why can the realized succession count be lower than the number I requested?

Later plantings are trimmed if their base field date would land after the modeled harvest end. The package avoids forcing plantings into a season window it has already marked as finished.

Why does hardening matter in the schedule?

Extension guidance commonly recommends a gradual outdoor transition before transplanting. The planner therefore reserves a separate hardening phase when you keep transplant production enabled.

Does the notes seed change my dates?

No. It only stabilizes the wording of the advisory note. The calendar dates come from the frost, crop, and timing inputs.

Are my planting details sent to a server for calculation?

The slug does not ship a dedicated server-side planner. Date math, schedule generation, and exports are produced in the browser session after the page assets load.

Glossary

Last spring frost
The average date of the final spring frost used as the early-season anchor for the plan.
First fall frost
The average autumn frost date used to cap or assess the late-season harvest window.
Direct sow
Planting seed straight into the bed instead of raising seedlings indoors first.
Hardening off
The gradual outdoor acclimation period before transplanting indoor-grown seedlings.
Succession
A later planting of the same crop meant to extend or reshape the harvest pattern.
Bed-prep lead
The number of days the planner schedules bed work before each field date.
Harvest buffer
The number of days between the modeled harvest end and the entered first fall frost.
Zone padding
The built-in number of days subtracted from the fall side of the season based on the selected zone.