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Can tomato compost be used for tulips?
Q I have lots of used tomato compost in this year’s growbags. Is it safe and suitable for growing tulip bulbs?
Tom Mason, Ipswich, Suffollk
A It should be fine to grow tulips in compost that was previously used for tomatoes, as they don’t share any host-specific pests or diseases.
However, do bear in mind that the compost may contain some non-specific pests, such as slugs and snails, and don’t use it if your tomato plants suffered from blight as it will contaminate the soil.
Tulips are not particularly hungry plants, but will appreciate some additional nutrients as the old compost may well have become starved.
You can do this by mixing it with new compost (I would do a 50:50 mix) or simply by adding slow-release fertiliser at the rate recommended by the manufacturer. There are advantages and disadvantages to both.
Mixing with new compost ensures that a reasonably good structure is maintained, which is important for water and nutrient retention, and drainage.
Compost tends to start to break down after a while and then behaves quite differently, not draining well and becoming incredibly difficult to rewet if it dries out.
On the other hand, this is quite a pricey thing to do as you need
