What is one major factor in determining the quality of Irish potatoes during growth?

The quality of Irish potatoes during growth is heavily influenced by soil structure around the plants. Soil structure refers to the arrangement of soil particles and the pore spaces between them, which directly affects root development, water retention, and nutrient availability. A well-structured soil allows for better aeration and drainage, creating an optimal environment for potato roots to grow. This promotes healthy tuber development as the roots can spread easily and efficiently access the nutrients they need to support growth.

Additionally, soil structure can affect how well water penetrates and is held in the soil, which is critical during different growth stages of the potato. Poor soil structure can lead to compaction, which restricts root growth and limits the availability of nutrients and water, ultimately impacting the size and quality of the potatoes produced.

While factors like humidity levels, soil compaction, and fertilizer application also play important roles in potato growth, they are not as directly related to the immediate environment and physical conditions affecting the roots of the potatoes as soil structure is.