If you want somebody else to do the scheduling for you, visit the sproutrobot.
If you want to create it yourself, here are step by step instructions.
First you need a calendar and to know what your frost free date is.
You can either use a wall calendar, create your own from an email program or word or excel, or get one off the internet. I would recommend either the one or two month per 8.5x11 page. Print all the months from Jan till June.
Mark on your calendar any significant events that you need to plan your planting around, times you will be traveling or so busy you are not taking the 30 minutes to throw some seeds in little cups. Maybe the week of your child's High School graduation would not be a good time to plant those last starts or to bring in a load of mulch. Next mark your frost free date. You can find it here.
Next you need to determine how many weeks BEFORE the frost free date to put the seeds in the planters so that they reach the appropriate size about the same time the outdoors reaches the appropriate temperature. You can read the back of the seed envelope, which is the best option because sometimes it will give information specific to that variety, like 'sow shallow' and it will tell the days to germination which helps you know when to re-plant any that didn't grow. If there is no or only limited info on the back of the seed packet, search it on the internet or check out this document. It has some great information and page 4 has a graph which tells how many weeks to transplant which is typically the same as how many weeks before the frost free date to plant your seeds. You can also get similar information off the Almanac page.
For Example, if:
My Frost Free Date is May 22nd.
Broccoli is transplanted at 5-7 weeks from the soil being worked. The soil can be worked usually a few weeks before the frost free date. I count back 8 weeks (middle of 5-7 + 2) and pick a day I am available. I will start my seeds on March 27th.
Tomatoes need to be transplanted 5-7 weeks from the frost free date. This will not be adjusted for 'workable soil' since tomatoes need warmth and will still likely get the walls of water or something similar. These seeds will be started on April 9th, six weeks (mid point of 5-7) from my frost free date.
Once you get these figured out, keep all your papers and notes. This will help you to make adjustments for when to start your seedling and an easier crop rotation the next year.
One of my calendar months looks like this:
Another thing you need to consider is if you grow with grow lamps/lights, your plants will likely get bigger faster and if you grow with natural light in a window, they will take longer. Plan for the type of situation you have. Nobody can tell you exactly for fail proof and sure what will work perfectly for you. You need to just jump in and try something.
I cannot say it enough:
When starting seeds, takes lots of notes. This way you can make appropriate adjustments the next year.
If your plants reach transplant size 2 months early....start later.
If your plants do not reach transplant size....start earlier.
If your plants reach transplant size, but you want them bigger....start earlier.
There are a lot of "if" and a lot of adjustments you can make to correct them, but you have to remember what was what in order to do that and next year is a long time away.
Good luck and happy planting!!
