We're rather lucky with fruit trees in Cambridge - so much of the city used to be orchards that even in a bad year its possible to fill a basket with wildling fruit throughout Summer and Autumn. Excluding, for the moment, the soft fruit (wild strawberries, patches of raspberries and hybrids thereof, etc.) the first really abundant fruit thats ripe each year is the cherry plum - usually some time around the start of July.
The name is a little off - its not a cherry, its really rather more like a plum. Known to the botanist as Prunus cerasifera, its like a small, usually sweet plum that you might find planted in parks and hedgerows. The trees tend to be small, rarely more than 15-25 feet high, and they're much favoured in planting schemes due to their early flowering - there's a dark red leaved cultivar that is really common here. The fruit are small, any colour from yellow to red (or even a very dark red) and in most respects are small (2-3cm) plums - and you can use them for everything you use plums for.
|Cherry plums in some of their colour forms - and a batch of cherry plum vodka|
As an aside, some distinguish between mirabelle and myrobalan, usually defining the former based on the colour or where they're from - and if you're one of those folk then good luck to you. I've found enough trees with characteristics between plum, damson, cherry plum and bullace to believe that the trees themselves are rather less fussy with such definitions than we are.
Anyway, now you know what you're looking for, the big question becomes what to do with them. They're a little bit less convenient than most cultivated plums in that he flesh clings to the stone. If you want to eat them just as they are and just spit the stone out like that of a cherry, no problem, but it makes other uses rather more difficult. But you can stone them and cook them like plums in crumble, pie, tart, whatever you like - but its more work.
I find that they make one of the best jams of the year (the internet is full of advice for making jam so I won't bore you with more of the same) - weigh the fruit out, add enough water to stop them sticking to the bottom of the pan, and cook to a pulp. Rub the pulp through a colander, and if you need boil the stones again in some more water to get the rest of the pulp off. Now add the same weight of jam sugar to that of the fruit, and a squeeze of lemon juice, and cook until you reach setting point. The colour of the jam depends on the cherry plums they use, but the red ones perhaps make the prettiest.
They also make a good wine, if homebrew is your thing. Again, whole books have been written giving methods and you'll find no end of advice online, but generally speaking its simple. Start out with 3lb of cherry plums and 2 3/4lb of sugar, plus a squeeze of lemon juice and a cup of strong, black tea for tannin, and a little yeast nutrient to produce a medium wine that can be white from yellow plums or rose from red ones. If you want to get technical about it a spoonfull of pectozyme really helps get the most out of the fruit when you start the process too - its not essential but you'll get a rounder, more full bodied wine.
If that all sounds too much like hard work you can use them for making a liqueur. Fill a jar with the cherry plums, pour vodka in until the gaps are all full, seal it up and put it in a cupboard for a few weeks. When you're fed up with waiting, pour off the vodka into a bowl and make up a small amount of sugar syrup. Add a little syrup to the vodka, stir it in, and taste - if it needs more sweetening, add more syrup, and when you're done bottle it.
Lastly, if you've still got a fridge full of berries after eating your fill and making jam and wine, make chutney. I've usually got my first glut of courgettes at the same time as the cherry plums arrive, and by adding beans, onions, raisins and the like you can make a chutney as good as any other - again, start by stewing the fruit down and rubbing the flesh off the stones. I don't believe in chutney having recipes as such, but if you want a good one, this one is as good as any I've seen.