Leek Rust (Puccinia porri) is probably the most devastating foliar disease to affect leeks. It is characterised by the rust coloured pin head sized pustules which cover the leaves. In severe attacks it can almost completely defoliate the older leaves leading to poor growth and subsequent low yields. Many rusts survive and spread by using an alternative host species to produce ‘resting spores’. However it is thought that leek rust is able to survive solely on leeks due to leeks being grown for 12 months of the year in the UK.  This ultimately this makes transmission from plant to plant a common problem.

Rusts are also so prolific it only takes a few leeks left in the ground in late spring to infect crops over a very wide area. The leek cultivar I have grown this year is ‘Philomene’, largely due to its robust upright growth. Its disease resistance has been very disappointing, and this is the second consecutive year my crop has become infected. My plan for next year will be to return to my tried and tested cultivar ‘Stamford’. This is not only very resistant to rust but it is also a vigorous grower.  Even a late September planting will produce large leeks by the following March.

But rust is not the only problem for me this year. I first became aware of this relatively new leek pest only when I topped and peeled my freshly dug up leeks.