Peach leaf curl is a significant fungal disease affecting peach, nectarine, and almond trees. It is endemic throughout the UK, and at its worst in areas with mild wet spring weather (which of course describes most of the UK!).
Apricot trees may also be affected, although the disease is much less virulent in apricots.
Perhaps surprisingly, almond trees are also affected by this disease - reflecting the fact that peaches and almonds are actually quite closely related (the blossom is very similar).
The disease is transmitted by fungal spores which are active during late-winter / early-spring and are carried in splashes of rain drops. The infection causes the leaves to curl and shrivel (often taking on a dull red tinge at the same time). Although the tree will often produce a second flush of leaves later in the spring, it will probably not produce any fruit because the disease weakens the tree. Weak trees are in turn susceptible to other problems.
There are no effective cures for this infection but fortunately there is an easy and highly effective way to prevent peach leaf curl - simply keep rain drops off the trees over winter and early spring.
If you have wall-trained trees just cover them over the winter and early spring with a frost fleece or similar. This is one reason why training peach and nectarine trees against a wall is such a good idea.
Peach trees grown in patio containers can also be protected, simply by keeping them indoors over the winter. Similarly if you are growing your peach trees in a greenhouse or polytunnel then you will be able to avoid it altogether.
Trees grown in the open are not as easy to protect, but it is worth trying to use a horticultural fleece to keep the rain off as many of the branches as you can. The disease does not really spread between leaves on the same tree, so even covering part of the tree will be a help.
Do not cover the tree too tightly, since you still want bees to be able to find the flowers to pollinate them.
Our variety pages describe the susceptibility of all the varieties we sell. However despite claims you may read for resistant varieties (notably Avalon Pride) it is best to assume that all peach and nectarine varieties are susceptible to a greater or lesser extent. Of the varieties we sell, Redhaven and Sanguine de Savoie have some resistance, whilst Saturn (the popular flat-peach) is very susceptible. Don't let that put you off Saturn, which is in other respects an excellent peach - just be sure to protect it from infection over the winter and early spring.