Home Page


 Annual Show

 Seasonal Hints



 Q & A Page

 Hints & Tips

 Plot Post

 Allotment Rules

 Useful Links

 Contact Us

All views expressed are the opinions of the author and are not necessarily those of the Society

  January 28th, 2019
Lichfield & District Allotments Society

High Peak

Potatoe Blight

Blight (Phytophtora Infestans) along with slugs is the most common cause of despair amongst potato growers. The problem starts when summer temperatures rise above 15C and humidity reaches above 90%, conditions are then perfect for the spread of blight. Secondly, the fungus has the ability to spread from plot to plot via air, water and soil. The third factor is that the spores can survive the winter and reactivate the following spring when the climatic conditions are again right.

In the south of England it is largely endemic and growers there fully expect to suffer from blight in all but the driest of years. In the midlands the situation is not so acute but we can expect to suffer from it at some point. 2007 was the worst year in recent memory with crop failures nationwide, although 2008 was classed as a wet summer we escaped the ravages of the fungus until the end of August by which time most had lifted their crops.

The fungus remains alive in infected tubers left lying around the plot, in compost heaps and even in those carefully stored sets that you intend to use for next years seed. The first signs are brown spots or welts appearing on the leaves, once spotted quick action is vital. Cut off all the stems & foliage an inch above the soil surface, if caught quickly this action should stop the spread of fungus to the tuber, clear away the rotting foliage so that the spores do not wash into the soil, do not be tempted to compost them, let the council deal with them instead! Finally, you might as well then lift your potatoes as they are not going to grow any larger without foliage and to leave them only increases the chance of slug and disease damage.

Once you have detected the disease, cut off the tops and lifted your potatoes you will have to check their condition on a regular basis, look out for soft wet patches with a telltale horrible smell, destroy these and any others that have been in contact with them.

So what else can you do, there are some products that you can spray on as a preventative measure throughout the growing season, but these are not a cure. Far better to grow resistant varieties and plant with ample space ( 3ft ) to allow free air movement between rows and ridge the rows as high as possible. The best potato cultivars which show the most resistance include:

Bambino Cara Cosmos Kondor Markies
Nadine Orla Pixie Sante Pentland
Premiere Robinta Romano Lady Balfour Sarpo Mira

Pat Bardon

Last Page   Last Page

  Top of Page
Published by:  Lichfield Web Design