A mobile application that builds on the ideas in the Growers Nation challenge to include a potential aphid prevalence climatology and early warning system for use by gardeners.


Aphids, also known as greenfly and blackfly, are sap-sucking insect pests. There are more than 500 aphid species inBritain.  Some species will only attack one or two plant species, but others will attack a wide range of plant hosts. Almost all plants are affected, including ornamental plants, vegetables and fruits, greenhouse plants and houseplants. They cause distorted growth and excrete a sticky substance on foliage, which allows the growth of sooty moulds. Some aphids also transmit viruses. There are many different insecticides and pesticides available to gardeners to combat aphid pests. However many people are choosing to garden more organically for health or environmental reasons and may wish to limit their use of pesticides. Knowledge of prevalent pest species for their local area and forecasts of when infestations may occur will help gardeners to apply the correct treatment and time their use, cutting down on the overall use of chemicals.

The challenge

To build an aphid forecasting component on to the current Growers Nation app, producing climatology maps of prevalence for different species of aphids across the UK based on known relationships between these aphid species and climate variables ie temperature degree days. Utilise these relationships and maps together with weather forecast data to produce operational forecasts of aphid prevalence (for different species) across UK.  This forecast could potentially be made available via the Met Office Weather Observation Website (WoW) system.


Data Resources(s)

This app will share some data sources with the Growers Nation app.  Specific data sources that may be of interest include:


Other data that would be useful but not yet sourced would be:

  • Sensitivities of different aphid species to climate variables i.e. Growing Degree Days (GDD are a measure of heat accumulation used by horticulturists, gardeners, and farmers to predict plant and pest development rates such as the date that a flower will bloom or a crop reach maturity)
  • Information on vegetation types susceptible to different aphid species

Further information

An academic article also exists which explains the relationship between the weather and aphid phenology, which may be of interest to those thinking of working on this challenge (email info[at]geohack.org for more information)

It’s All Over!
Thanks to everyone who helped make FOSS4G 2013 a success!