Hi, I have also had difficulty in getting carrots to germinate, especially in my regular home gardens, I always got 2 inch high greens with tiny baby carrots or none at all.
But whay works great, at the horse farm, is to grow them in a very old manure/hay/sawdust dump pile. I dig out all the weeds, and grass, and burdock (takes years to get rid of)(yikes) , then when it is relatively cleared, I have a 1-3 foot pile of pure beautiful crumbly compost. It is so soft that the carrots can grow straight down without anything obstructing them. I was just weeding yesterday and pulled up a nantes that was already 4-5 inches tall! Basically, I start in spring- mid April in ( Massachusetts) and just randomly sew the seeds by hand, I rarely bother with them, if they grow, great! I don't worry about rows or thinning. I do serial sewing throughout the summer too. Last year I threw some seed down randomly in August, and in late winter , early spring this year i found a whole bunch of small to medium carrots that my horses fuly enjoyed!
Also My most recent manure pile 3 years of collecting with 1 year of no new manure was made into a 15 foot round 4 foot deep tapered potato garden. i am so excited, it is my best garden this year!
So if you do not have access to a farm, and live in a rgular backyard, I would definately try a deep raised garden, at least 2 feet deep. Also buy three times as much seed as you think you need with carrots since they are so tiny and ? what the germination rates are for the particular seeds you purchase. Hope this helps. Plant some more and let us know. I'm going to plant some more this morning too! Good Luck! LP
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