Pickled Beetroot

Duncan was given two carrier bags by a guy at work, and he of course brought them home for me. one contained potatoes, and one contained beetroot. Potatoes, no problem. Beetroot? How am I going to use up half a dozen beetroot? Well, they were free, I've got enough to play with, and some jam jars left over, I'll try pickling them.
So, I go searching, read a few recipes, and come up with something I hope will work.
First, cook the beetroot. I baked them rather than boiling them. Wash them thoroughly, cut of most of the root and leaves (but leave some on), place in a covered casserole dish and bake at about 180C for anything between 1 and 2 hours depending on the size.
Once the beetroot is cooked, leave it to cool slightly, until till hot but just cool enough to handle. While they're cooling, sterilise the jars* and make the pickling liquid.
From my reading of various recipes, the pickling liquid is basically vinegar with various additions. The vinegar can be diluted. I used 200ml of cider vinegar and 100ml water. To this I added some juniper berries, cloves, mustard seed and a little sugar. Place this over a medium heat.
While the pickling liquid is heating, slice the beetroot. My jars are quite small, so I quartered the beetroot before slicing them. once the beetroot are prepared, get the jars out of the oven and bring the liquid to the boil. Pack the beetroot into the jars, pour over the liquid - making sure the jars are full right up - and seal.
I unfortunately, didn't have quire enough liquid for the three jars. The beetroot was covered in all three before sealing, but not right to the top. I thought it would be OK, but either the liquid evaporates or the beetroot absorbs it. So it's now a 'fridge pickle', needing to be eaten quite soon. The one we opened on Thursday seemed to be fine, although a little sharp for my taste (more sugar needed in the liquid? Different type of vinegar?) We'll see how the other ones have held up when they get opened.

*Turn the oven down to about 150C, wash the jars in hot soapy water (rinse in very hot water to get rid of the soap - not a good addition to anything), and put upside down in the oven - the same process as sterilising the jars for jam.