Plant Doctor Archive

 WE live in Central Otago — very cold and frosty. However, my question is about tomatoes grown in a glass house. My Dad grows tomatoes in polythene bags in a glass house but they are always very hard and green around the stalk end. Please help.

 THERE are several reasons for this to happen. Too much sunlight, too dry or too much potash.

If it is sunlight, shade cloth or white-out on the glasshouse will help. Apply sulphate of ammonia to correct the nutrient imbalance if it is too much potash. Water regularly, especially as they are grown in planter bags — this could be as regularly as twice a day in summer.

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