Talk to us!
Hello, we are the scientific
team at Smart Fertilizer
How can we help you?
I have a question!
If you need agronomist consultation,
please visit our knowledge hub forum
Create a topic with your question
and team of our lead agronomists
will provide you with expert advice.

How can we call you?


Join Our Forum Now And
Ask Any Question FOR FREE
Become a member of Smart Fertilizer Knowledge Hub
Plant Nutrition Experts Community
Thank you for joining and welcome to our forum!
Join Our Forum Now And
Ask Any Question FOR FREE
Become a member of Smart Fertilizer Knowledge Hub
Plant Nutrition Experts Community
Thank you for joining and welcome to our forum!

Gray Mold is a disease commonly present in grape and strawberry crops. It is produced by a fungus that can infect a vast quantity of crop species causing serious problems in plant health and reduced yields. However, is it always unwelcome? Read on to discover more about this disease, the fungus Botrytis cinerea and how to get rid of it when unwanted.

1.    What causes gray mold?

This disease is commonly known as gray mold due to the colour observed in the crops when the plants are infected. The structures are made by the fungus Botrytis cinerea, whose spores, when present together in a high amount, shows a grey-type colour. This fungus reproduces both sexually, forming structures called aphotecio, and asexually, with reproduction spreading spores formed in conidiophores. You may have seen the image of conidiophores in which the fungal spores, called conidia, are arranged in a tree-like manner in the external area of this structure.

Botrytis cinerea Conidiophore with conidia stained with lactic acid. 400x amplification. The scale bar represents 10µm. Author:  Vysoká škola chemicko-technologická v Praze.

An accurate fertilization program can be the salvation of your crop, since Botrytis spores do not germinate in healthy plants, only in those presenting any damage or insect wounds. SMART Fertilizer Software provides personalized advice to provide your plants with the most efficient amount of nutrients. It helps them grow strong and healthy to avoid this kind of disease. If you are growing grapes or strawberries, you need to take good care to avoid this fungus.

Easily create your fertilization plan with our software
Start Using and Increase Your Harvest up to 40%
Create your plan

In warm areas, the wind can spread the conidia all over the field, infecting a large group of plants, even those far from the disease origin. The fungus does not only grow in warm areas but also when the temperature is as cold as 4 ⁰C. The main factor that will enable fungai development, apart from the health of your plants, is relative humidity, and also an abundance of rain leaving the fruit wet for long periods.

2.    Can we take advantage of this infection?

For the production of certain types of wines, the presence of Botrytis is required. However, the infection needs to be well controlled by the farmer manipulating the fungus development. This process is called Noble rot. This procedure starts with a high relative humidity that promotes the Botrytis infection in the bunches of grapes. Once the fungus has spread all over the fruit, it must suffer a dramatic drop in relative humidity. During an extended dry period, the fruits’ water content evaporates through the perforations that Botrytis caused in their skin. This increases the sugar content making a high quality wine, with a sweet flavour and bitter finish. According to the experts, they taste like honey, beeswax, ginger and honeysuckle, for example the Tokaji Hungarian wine. This technique is also used with grape raisins.

Bunche of grapes suffering Noble rot by Botrytis cinerea. Author: Vinoble

3.    Getting rid of unwanted Botrytis development

In most cases, the development of Botrytis cinerea is unwelcome and effort is required to remove the problem. In general, the best way of avoiding diseases and pests is to know the preferences of the infecting organism. In this case, Botrytis cinerea prefers wet environment and warm temperatures.

The main cultural control recommendation is to promote the aeration between plants to dry Botrytis spores and the structures it may form when trying to infect your crop. A thorough study of the field dimensions should be carried out prior to plantation; the plants should be sown keeping a prudent distance, while making the best use of the space in order to be efficient. In addition, biological and chemical controls are available in the market.

You can count on SMART Fertilizer experts for support and advice during the entire growing lifecycle of your crop. You can also ask questions and share experiences for free with the community at



  • Recommends the ideal fertilizer mixture/ blends
  • Saves up to 50% on fertilizer costs
  • Comprehensive data on hundreds of crop varieties
  • Interprets test results for any extraction method

Try Our Software Now