Keeping Frost Off Young Tomato Plants

Last week I purchased a few tomato, pepper and chilli plants, but was a little worried about any frost that we might have in late March. A light frost was forecast this week, so I decided to hang some fleece in the poly tunnel, which is already lined with bubble wrap, but no heating.
I used a minimum/ maximum thermometer in the poly tunnel to check on the temperatures and it did drop to zero inside. Luckily, no frost damage occurred, but just as well I took the precaution.

There is a big difference in the tomato plants in just over a week from when I purchased them. They were starting to get 'leggy' so spacing them out helped a lot and I planted them in the raised beds today.
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