You've tried a garden planner before. You entered your zone, got a generic calendar, and realized your tomatoes were two weeks late because "Zone 5" covers a 10-degree temperature range and your city is at the cold end of it.
Or you paid for a subscription, cancelled when life got busy, and lost every garden plan you'd built.
Or you opened a "gardening AI" and asked when to start peppers, and it gave you the same answer it would give anyone on earth.
This post compares the three most popular tools in the category in 2026. I built GrowSmart, so the verdict isn't neutral. But I'll tell you honestly which tool fits which gardener, including when it isn't us.
Most comparison posts rank tools by affiliate commission. This one doesn't.
The verdict, if you're in a hurry
Pick GrowVeg if you garden in the US or UK, want the deepest plant variety database available, and don't mind losing access if you cancel.
Pick Seedtime if you garden in the US, want a real free tier, and prefer a task-driven calendar over a visual bed planner.
Pick GrowSmart if you want planting dates that actually match your city (not a zone average), a tool that works offline in the garden, and an AI assistant that can look at a photo of a sick plant and tell you what's wrong.
If you want to try GrowSmart free, start here. No account, no credit card, no trial timer. Enter your city and you'll see your exact planting dates in under 30 seconds.
At a glance
| GrowVeg | Seedtime | GrowSmart | |
|---|---|---|---|
| Starting price | ~$45 USD/year | Free, from ~$4.55/month | Free, CA$4.99/month |
| Real free tier | 7-day trial only | Yes | Yes (limited) |
| Works offline | No | No | Yes |
| AI photo diagnosis | No | No | Yes |
| Best for | Largest plant database | US-focused, task-driven | City-specific frost dates |
What makes GrowSmart different
Every garden planner has added an "AI assistant" in the past year. Most are generic chatbots with a gardening system prompt. They don't know your zone, your frost dates, or what you're actually growing. You ask a question, they give you a Wikipedia-style answer.
Sage is different. Sage reads your actual garden before answering. It knows you're in Toronto, Zone 5b, with a last frost of May 9. It knows you planted tomatoes two weeks ago. It knows your salsa bed has cilantro going to seed, and that your peach tree is at pink bud stage. When you ask "should I water today?" it answers for your garden, on your day, with your weather.
Sage can also:
Identify plant problems from a photo. Take a picture of a yellowing leaf or a suspicious bug, and Sage returns a confidence-ranked diagnosis with treatment options. It runs on Kindwise's crop.health API, the same tool used by commercial agricultural consultants in the field.
Design and apply garden layouts. Tell Sage "design a shade bed with cool-season crops," and it proposes a complete layout using companion planting rules and square-foot spacing. Review it, tap Apply, and it fills your bed.
Remember your garden year over year. Sage recalls what you grew last season so it can warn you about rotation conflicts and suggest improvements for next year.
Plan succession sowings automatically. Ask "what can I sow after lettuce?" and Sage gives you a ranked list of follow-on crops with exact dates based on your frost window.
It's not a chatbot that happens to know gardening. It's a garden planning tool that happens to converse. The difference shows up the first time you ask it something specific and it answers like someone who actually knows your garden, because it does.
We call it a master gardener in your pocket because that's what we built it to be.
If you want to try Sage free, start here. Three Sage questions are free for every user, no account required.
GrowVeg
Best for: experienced gardeners who want the most comprehensive plant database available and are willing to pay annually for a mature, well-supported tool.
GrowVeg has been around since 2007 and is owned by the team behind the Old Farmer's Almanac. That history shows in the plant database: 408 species with 21,400 varieties, each with detailed growing information. Their companion planting system references 502 scientific studies, which is genuinely impressive and rare in the category.
The visual planner is polished. You drag plant icons onto a bed layout, and the system calculates spacing, warns you about crop rotation conflicts based on up to five years of history, and generates a plant list with quantities and planting dates specific to your location.
What you get: visual bed planner with automatic spacing, crop rotation warnings, succession planting, email reminders, 441 how-to videos, garden journal, support from trained gardening experts, and pest advice for 408 plant species.
What to know:
- No free tier after the 7-day trial. If you cancel your subscription, you lose access to your garden plans and historical data until you resubscribe.
- Annual subscription pricing, roughly $45 USD per year or $70 for two years.
- Web-based and iPad. No Android or iPhone app.
- US and UK versions are separate sites.
If you're in the US or UK, garden seriously, and want the most comprehensive tool on the market, GrowVeg is genuinely excellent. The pay-to-access-your-own-data model doesn't suit everyone, but it works for gardeners who garden every year and value plant variety depth.
Seedtime
Best for: US home gardeners who want a task-driven calendar with a real free tier, and who appreciate a community-funded development approach.
Seedtime started as a crowdfunded project and has grown into a solid mid-tier garden planner with a genuinely useful free account. There's no credit card required to sign up, and the free tier gives you access to the planting calendar, task list, journal, and 3,000+ pre-installed crop varieties.
The app auto-generates a task list from your planting calendar. If you miss a date, it reschedules automatically. An AI assistant called Sprout answers gardening questions in a text chat, and the Classroom has short video lessons tied to specific tasks.
What you get: planting calendar with drag-and-drop, auto-compiled task list, journal with photo attachments, AI Sprout bot, video classroom, mobile apps for iOS and Android, 30-day money-back guarantee on paid plans.
What to know:
- Free tier is real and permanent, but the visual bed layout planner is paid-only.
- Premium starts around $4.55 USD/month. Higher tiers with bed layouts can run $99 to $150 per year.
- No fruit trees, berries, or perennials in the built-in database. You can add them manually.
- No crop rotation warnings.
- US-focused. Not ideal for gardeners outside North America.
- The Sprout bot answers general gardening questions, but it doesn't read your specific garden state the way Sage does.
If you garden in the US, want mobile access, and like the idea of a tool that started as a community project, Seedtime is a good pick. The free tier alone is more generous than most competitors.
GrowSmart
Best for: gardeners who want accurate planting dates tied to their specific city, a tool that works offline in the garden, and an AI assistant that can diagnose plant problems from a photo. Especially well-suited for Canadian, UK, and European gardeners.
We built GrowSmart because most garden planners treat "Zone 5" as a single thing. In reality, Zone 5 in Toronto behaves differently from Zone 5 in Denver, and Zone 5 in the Cotswolds is different again. GrowSmart stores exact last-frost and first-frost dates for more than 1,400 cities across Canada, the US, the UK, and continental Europe. Our data comes from Natural Resources Canada, USDA, and the Royal Horticultural Society.
About the plant database: we focus on the plants most home gardeners actually grow, and we enrich each one with detailed data. Every plant in GrowSmart has 12 data fields (mature size, square-foot spacing, sun hours, water needs, companion partners, rotation family, overwintering method, and more) plus targeted care warnings for common problems. Depth over breadth. We're adding new plants steadily, and if there's one missing you need, we'll add it.
What you get: exact frost dates for your city, 3-season planning (spring, summer, fall), companion planting with explanations, automated succession planting, crop rotation logic, fruit trees and perennials, offline-first PWA that works in the garden without signal, AI assistant with photo diagnosis and layout design, and a free tier that requires no account to try.
What to know:
- Our plant database is smaller than GrowVeg's catalog by design. Each plant gets deep treatment rather than shallow variety coverage.
- Free tier is limited to 10 plants and spring-only planning. Full access requires Pro.
- Pricing: CA$4.99 per month or CA$39 per year for Pro. CA$7.99 per month or CA$59 per year for Pro with Sage, our AI master gardener.
- No native iOS or Android app yet. The PWA installs directly from any browser on any device. Works like a native app, updates instantly.
- Canadian-founded. Strongest coverage in Canada (200+ cities and growing), with expanding UK and European city data.
If your priority is having your planting calendar match your actual city's climate, GrowSmart is built for you. If you want a tool that works when you're out in the garden without signal, the offline-first PWA genuinely works.
Try GrowSmart free. No account required.
Questions that actually matter
How accurate are the planting dates?
This is the most important question, and most comparisons skip it. "Zone 5" is a 10°F range. Two cities in the same zone can have last-frost dates three weeks apart. In gardening, three weeks is the difference between a harvest and a loss.
GrowVeg uses nearest-weather-station frost dates. Generally accurate for established US and UK locations.
Seedtime is zone-based. All Zone 5 users get the same dates regardless of whether they're in coastal or inland Zone 5.
GrowSmart uses city-specific frost data from Natural Resources Canada, USDA, and the Royal Horticultural Society. The 1,400-city database is the largest city-specific frost catalog in any of these three tools.
What happens if I cancel?
GrowVeg: You lose access to your plans while your subscription is inactive. Your data is retained and becomes accessible again if you resubscribe.
Seedtime: Free tier remains accessible. Paid features revert.
GrowSmart: Your local data stays on your device. Pro features revert but your garden plans, task history, and personal data remain viewable.
Does it work offline?
GrowVeg: No.
Seedtime: No.
GrowSmart: Yes. Full offline functionality via the PWA. Changes you make in the garden sync automatically when you reconnect.
Can it identify plant diseases from a photo?
GrowVeg: No.
Seedtime: No, but the Sprout AI bot answers text questions.
GrowSmart: Yes, on the Pro with Sage tier. Sage uses Kindwise's crop.health API, the same professional-grade diagnosis tool used by commercial agricultural consultants.
How do I try each one without committing?
GrowVeg: 7-day free trial (no credit card required).
Seedtime: Free account, no credit card, no trial period.
GrowSmart: Free tier. No account required, no credit card, no trial timer. Enter your city and start planning.
Why I built GrowSmart
I'm Amanda. I'm a foster mom and a full-time accountant. I live in Zone 5b Ontario with raised beds, an orchard, perennials, and herbs. I built GrowSmart in the evenings and weekends because I kept losing tomatoes to late frosts I should have seen coming, and I couldn't find a planner that understood my actual city rather than a zone average.
I built Sage because I wanted a gardening expert I could ask at 10 PM without feeling like I was bothering someone. And I made the free tier real because nobody should have to pay to find out if a tool works for them.
If you try GrowSmart and it's not the right fit, use one of the other two. They're solid tools. I'd rather you garden well than feel stuck with us.
How to pick the one that fits you
The honest answer depends on how you actually garden.
If you garden in the US or UK and want the deepest plant variety catalog: GrowVeg.
If you garden in the US and want a free tool that's actually useful: Seedtime.
If you garden in Canada, the UK, or Europe, or you want planting dates that match your specific city, or you want an AI that actually knows your garden: GrowSmart.
Pick the one that matches how you actually garden, not the one a "best of 2026" list ranked highest based on affiliate commissions.
Try GrowSmart free. No account, no credit card, no trial timer. Enter your city and see your exact planting dates in under 30 seconds. Then ask Sage anything. A master gardener, in your pocket.