Establish the Perfect Growing Conditions

March 31, 2021

Establish the Perfect Growing Conditions

2 minute read

April is the ideal month to plan which vegetables and herbs you’re going to grow. To give your seeds the best chance of germinating and eventually producing an abundant harvest, it’s important to get the growing conditions right from the very start. There is also still the chance of frost at night which will need to be monitored. Most vegetables and herbs will need to be sown indoors or undercover, and kept there until all risk of frost has passed.

Three factors that can be monitored to ensure optimal germination and growing conditions are soil temperature, air temperature and humidity.

Soil Temperature

The ideal soil temperature will vary depending on what you’re growing, so it’s a good idea to check beforehand. In general, most seeds won’t germinate if the soil temperature is below 7°C. To determine the soil temperature and ensure readings are accurate, use a good quality soil thermometer. We suggest a measuring depth of around 2 inches and to record the temperature twice a day.

Air Temperature

It’s important to remember that the air temperature will likely be different to the soil temperature, whether it’s indoors or in a greenhouse. A temperature of 18-21°C will be ideal for growing most vegetables and herbs. Monitor the temperature of all growing locations. Use a weather station with multiple sensors to keep track of each area and note the minimum and maximum readings. Once the night temperature is regularly reaching 7°C, seedlings can start to go outside.


Monitor the humidity levels of your growing spaces throughout the season, whether it’s indoors or outdoors. Seeds will need moisture to germinate, so using a propagator will ensure that humidity levels are high enough. However, if seedlings are kept in too humid conditions, it can cause rot or mold problems, which is why it’s important to actively monitor levels. Use a humidity sensor for smaller areas such as propagators, or a hygrometer dial for a greenhouse or outside.

We love to see how your seedlings are coming along so do share a picture with us on Facebook, Twitter or Instagram.

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