You’ve got the seeds, you’ve got the enthusiasm and if you’re like most gardeners, you’ve also got about 47 open tabs with conflicting advice about when to start everything.
Close those tabs. This weekend, I spent a lot of time with my seeds and my nemesis—ChatGPT—commanding it to come up with the perfect seed-starting schedule for me. And now it can create a perfect seed starting schedule for you.
Table of Contents
With AI
Instead of squinting at the back of a seed packet, doing questionable math, and then hoping for the best I'm going to show you how to make a completely customized seed starting schedule instantly by using one simple AI command.
You'll be a seed starting star - the accolades from friends and family will be an embarrassment.
Artificial intelligence is only as helpful as the commands you give it. I played around over the weekend refining my commands until I got an easy to read seed starting schedule with all the information I wanted for my seeds.
Here's the beauty.
Seed Starting Schedules
If you're only starting 3 or 4 different things it's not a big deal. Your brain is probably still agile enough to keep a few planting days straight and the plants alive.
But once you delve into needing BOTH hands to count how many types of seeds you're starting then you need to plan.
You need a schedule because if you’ve ever tried seeding multiple seeds on multiple planting dates over multiple months without any plan, you know how quickly things can death spiral.
I Compared It Against My Own Experience
After AI created the schedule, I crossed referenced it with my own hand written schedules from the past few years. I *know* the best time for me to start beets, based on my trial and error experience over the years, is the middle of March.
The artificial intelligence scheduled recommended I plant beets on March 13.
Perfect.
How It Works (and YES it's Free)
The schedule is tailored specifically to you. It takes into account your USDA growing zone (or equivalent), your last frost date, and factors in germination times for any and all plants you want to grow from seed.
Would you like to save this stuff?
We'll email you this post, so you can refer to it later.
🌱 You’ll never start too early or too late—which means stronger plants and better yields.
🌡 You’ll know at a glance if your seed needs a heating pad to start it.
💡 You won’t have to keep Googling “Do onions need light to germinate?” (Spoiler: They do.)
📆 Everything is sorted by start date, making it incredibly easy to follow.
Get Your Own Custom Seed-Starting Schedule
You don’t have to wing it this year. You don’t even have to make a spreadsheet. Just tell ChatGPT your zone, last frost date, and the plants you’re growing, and it will generate a perfectly timed seed-starting schedule for you.
Use this exact command to get yours:
Copy and paste the command below into ChatGPT. Then replace anything inside of brackets with YOUR information.
"Create a customized seed-starting schedule for me based on my USDA hardiness zone and the plants I want to grow. I am in USDA Zone [X] with a last frost date of [Month, Day]. Please generate a detailed schedule including: Plant name, Start Date, Method (Indoor/Direct Sow), Planting Out Date, Days to Germination, Optimal Temperature (both °C and °F), and Light Requirement (Light or Dark for germination). My plant list includes: [List your plants here]. Make sure the schedule is formatted concisely and sorted by start date."
🌱✨
It will analyze for a moment and then create something like this ...
Double-Checking ChatGPT’s Answers
I always like to double-check any information I get from ChatGPT. After it gives me an answer, I follow up with this simple command:
"Double-check that information to confirm it's accurate."
If you’d like, you can copy and paste your schedule into an email to yourself or you can download the information and put it into whatever your favourite spreadsheet is.
I used Google Sheets to create a schedule that will print on one page of paper.
I had to mess around with the margins to get it to fit on a single letter size sheet of paper.
Use your schedule as a guide and take notes this year if things don't work out. But this will be an excellent starting point and guideline for your plantings for years to come.
I think. I mean, this is gardening and all hell could break loose at any moment.
p.s. The shelf over my right shoulder holds some of my favourite books of all time.
Susan Warren
Oooog what a neat little tool to have at our paws. I too got a bit carried away this afternoon asking one question right after another. Heck, I thought someone was sitting here giving me the answers. Better than any Google search I have ever used. This chat thing just might put the hurting on all these other search engines.
Thank you so much for the great tip.
Susan, Richmond, VA
Lost & Confused
Stupid question from a semi-tech-virgin-ish, 😂, what is this ChatGPT thingy??
Karen
ChatGPT is an artificial intelligence system. It's kind of like Google. You can search for Chat GPT and it will come up. You start an account and then ask it any question or direct it to do anything and it does. Go search it and you'll see what I mean. :) ~ karen!
Terry Rutherford
I’ve spent the afternoon playing with this. I find March an odd choice for tomatoes, which have always been perfect started in April indoors. Likewise, I went with your guidelines on onions over their March 15 choice. April was so hot last year the bunching onions bolted so early seems the right guideline! I shall take your beet guidance as well. Because I now seem to need 60 days in March (and a separate house) to start seeds, I added an additional instruction to Chat GPT, to “choose direct seed if it’s a reasonable option.” Phew, that’s better. So if anyone is overloaded, may I suggest you add that to the instruction. Karen, again, thank you so much for this! The tables imported to Apple Spreadsheet perfectly and printed beautifully, if anyone is worried about learning a new Google app.
Karen
I'm doing beets and onions earlier and earlier because the last several springs have been cool, cool, cool and then BANG heatwave until August. We don't have a gradual warm up like we used to. I start as many inside as I can because it's too risky to start them direct when the garden isn't at my house. I also had it create a direct seed second planting schedule. ~ karen!
Delin Thompson
“I sincerely appreciate the invaluable information you shared. Your insights have been incredibly helpful, and I’m truly grateful for your time and effort. Thank you!” That was chatGPT generated, but it is what I feel in my heart ;)
Hello hello yeah right now OK bye
Karen
Thanks to you and Chat! ~ karen
Judy
Wow. All I can say is wow. This is a great push to overcome my procrastination. Thank you SO MUCH Karen.
Karen
You're welcome! ~ karen
Kate K
Thank you-Thank you-Thank you!
It worked exactly as you said it would. Its shocking how quickly my plan was generated. I have spent countless hours trying to put this list together in past years. ChatGPT did it in less than 5 minutes.
I'm sure generating the perfect prompt was time consuming but you nailed it.
Truly-Thank you!
Karen
That's great! Just make sure you double check the dates. It's smart, but it's also not so smart sometimes. ~ karen!
CathyR
I’ve all but given up on planting anything here in Arizona because by May 1 it’s all burned to a crisp. Except my Thyme which has quadrupled in 5 years. Loves the heat, doesn’t mind 20°F.
I don’t think I’ve clapped eyes on a recent pic of you so I’m wondering why you chose one from 35 yrs ago…🙃😉
CathyR
Ooops, meant to say Rosemary, I’m considering planting some Thyme next to it.
Rebecca
Wow! Thank you so much for this. I have avoided the AI but thought this would be a good thing to try. I am so glad I did and never would have without your clear template.
Kasia
Brilliant. Awesome. And THANK YOU!! :)
jani
Ah! This is gold. Thanks for doing the hard work.
Elizabeth
Fascinating! I'm going to share this post with my local FB gardening group! Thanks!
PS... I love to see bookshelves with actual books in them. I've been a reader my entire life (now 66 yrs old), and I see pictures of bookshelves with nothing but bric-a-brac in them, not a book in sight! So, go you! Lol
Carol Halliwell
Did it in minutes! Thank you Karen! Now I have a ChatGPT account to use for other stuff.
Gina
My gosh - this is the coolest thing ever. In less than five minutes, I have already created a planting schedule spreadsheet for my own garden. Mind blown moment. :0 Complete brilliance. I already had all of my plants in a spreadsheet showing the variety, kind of plant (tomato, bean, squash herb) so it was easy for me to plug in the plants I plan to grow. Seriously amazing... Thank you, thank you, thank you for showing me how to do this.
Karen
You're welcome Gina! It's kindda great, isn't it? ~ karen!
Holly
Only one problem...when IS the last frost date for a specific zone? Once upon a time I knew mine was around the Victoria Day weekend. Nowadays it could be (and has been) early May - or mid May - or early June (that one was a real killer frost) - or who knows when? Pick the wrong date and ChatGPT will be just as useless as my own calculations. The joys of climate change.
But thanks anyway for the post - it's really neat to see how AI can work.
Karen
Well, nobody has ever known when their frost date will truly be. It's always just been a prediction based on history. You can Google when your last frost date is predicted to be. But yes, it's always going to be a general guess. ~ karen!
Linda
That is SO COOL! I wonder if it would go one step further and put the list in chronological order by start date. 🤔 My son has been trying to get us to try Chat GTP for a few months…can’t wait to share this with him! Thanks, Karen!
Karen
Hi Linda. It should automatically generate chronologically by start date. If it doesn't, you can just say "put in chronological order by planting date" ~ karen!
Terry Rutherford
This is fantastic! You’re a genius, with a great haircut too, but you knew that. I may also then ask Chat GPT to lay out our 20 beds to take into account companion/ripening date/height of our hundreds of seedlings (yes it’s big but fun and tariff-free)! (Freaking Ontario voters, btw. ) Enjoy this very Spring-like weather!
Karen
Thanks Terry. Have a good weekend. The onions sprouted last night so there's no turning back. ~ karen!
Hettie
I copied and pasted as directed and found all the info I need. Thanks, Karen! You're a whiz! :)
M
Very cool, but you don’t have to use your nemesis. Do a search for “Seedtime” and they have a fantastic free garden calendar. It’s also an app, but for now the site has more functionality. It’s also more than a calendar. I have no affiliation, just found it recently and squealed. Then had no serious gardening friends to tell till now. It’s USA based, but hope it works for Canada too.
:-)
Marieagg
Not helpful for me unfortunately. The first crop I entered required me to upgrade to a paid version.
Marieagg
Oh I was replying to M in regards to the Seedtime planner NOT ChatGPT AI. The AI version is FABULOUS!!
Re: this comment:
Marieagg March 04, 2025 at 10:48 am
Not helpful for me unfortunately. The first crop I entered required me to upgrade to a paid version.
Karen
Hi Marieagg. You shouldn't have to upgrade. Chat GPT allows a certain number of tasks per day for free. If you made a lot of changes it probably took up a lot of your tasks. You just need to wait until the next day and you can pick up where you left off. ~ karen
Maggie
Thanks. Good excuse for me to start ChatGPT.
Yes. Even before reading article I scoped out the books. (And your hidden storage units. Which have always fascinated me).
I like your hair longer like this. Shows off your pretty hair.
Paula Beattie
Awesome, thank you. Btw your hair looks great!
Gigi
OF course I was checking out your books, counting how many I’ve read too! This is a Godsend gardening tool and can’t wait to spend the day tomorrow working up our plan. Thank you! Now, if I can just figure out how/what ChatGpt works! Boycotting spending anything tomorrow, so this is the perfect antidote.
Isn’t it also about time for a 2025 Book/show recommendations speaking of a full bookcase?
Marc Greenstein
Great information on the seeds, will be sure to use it accordingly. Thanks for all your advice on so many things! And since someone else commented, love the new look! Had to look twice to make sure it was you!
Karen
It is as a matter of fact! I'm just compiling my lists. :) ~ karen!
Cindy in Denver
This is ingenious and helpful but I just started most of my seeds on Monday and don’t get too worried about the indoor start dates, because seriously, were those giant tomato plants at the garden shop started 8-10 weeks earlier? Not a chance. And I have a short growing season in Colorado so my plantings need all the help they can get. I will try to use AI to help me with a companion planting plan. My parsley and rosemary never looked better after I separated them from my other herbs.
Karen
Hi Cindy! The issue with starting plants too early is they take a lot of space in the grow room and it's a lot harder to keep the plants healthy and happy under lights when they're more mature. But sure, you can plant them whenever you like and hope for the best. It's gardening. There's no predicting what will work and what won't so just do what you want.😆 ~ karen!
Karen
Thanks Paula! It drives me crazy, lol. ~ karen!