My experience with growing carrots has hitherto not been crowned with glory. Most often the Carrot Root Fly did so much damage that the crop was very sparse. So much so that I gave up growing carrots altogether. Even when I covered them with Enviromesh they didn't do very well. I felt that the mesh prevented enough light getting to the veg underneath, and it was hard to apply the correct amount of water. And then I won a tall wooden planter, and my fortunes changed.
The planter enables me to grow carrots about three feet above ground level, thus avoiding the worst of the low-flying flies. It's not 100% effective, but still much better than anything else I have tried. I sow the carrot seeds into black plastic crates, two of which which fit neatly into the planter. This means that I can replace them whenever I need to. Last year I over-wintered the Strawberries in it.
I started growing carrots this way 3 years ago. The first year I had modest success (I considered that anything was better than nothing); last year the crop was poor because of the dull wet conditions during Summer, but this year it has all come good. I sowed three different types of carrot seed, all miniature / fast-growing types rather than maincrop ones, simply because space is so limited. I chose "Mini Finger", "Mignon" and "Amsterdam III Sprint". One of the boxes had just Mignon, but the other box had a mix of the other two types.
"Mignon" produced a very small amount of foliage and I though it wasn't doing very well, but when I pulled the first one to see what they were like I was pleasantly surprised. There was a lovely crop of short plump carrots:
They were also the first to mature. Sown on 29th March and first ones harvested on 13th July.
In retrospect I realise that the ones I labelled in a previous post"Amsterdam III Sprint" were more likely "Mini Finger". They are very long and slender. (Like a pianist's fingers maybe!)
Now I have harvested the first carrots of the third variety, which I'm pretty sure is "Amsterdam III Sprint" (Yes, I know I have said that before...)
These ones are the biggest of the three types - almost big enough to be a maincrop type. Again, I was surprised to see how big they were: from above they don't look much, when when they come out of the ground they are bigger than I had dared to hope.
As my photos demonstrate, the carrots have all been well-nigh perfect. There have been literally a couple with a bit of fly damage, but not enough to be significant. I seriously believe that my success with these carrots is due to their elevation. They were not protected in any other way, and they were grown in perfectly normal proprietary compost. I think that the weather may have played a part (it usually does). Perhaps the very cold conditions in the Spring meant a late arrival for the flies, and the warm sunny weather during July helped the carrots to grow strongly and get big. Whatever the reason, I consider this year's carrot crop to have been a huge success.