If we are lucky, we have warmth in the day, but the nights can still be cold. As our ancestors recognised, it is a month that can easily turn back into winter. If I look at the past few weeks, the day temps have been up in the high teens, but the nights have been down almost to zero on some occasions. If you recognise that this is quite a large margin of difference, then you will realise just how remarkable plants are. Then you have the rain, hail and frosts to contend with too.
All this proves that the soil is still not very warm - hence the old custom of putting your bare elbow or perhaps your bare bottom on the soil, to see if it is ready for some of the more delicate plants. Some plants like Cymbidium orchids need a few cold days to help them flower, but a frost is definitely a no-no.
I am quite often frustrated by the weather news on the TV or internet as it is massively generalized to cover several hundred square miles - although I must admit they have got better in recent years. Once, in the middle of the last decade, whilst living in Norfolk, the weather girl reported it was going to be a lovely dry night, yet outside my window some 20 miles from her studio, the rain was hammering down. Did I see a hint of embarrassment on the poor girls face? In those days, my obsessive temperament noted they had only got it accurate on 15 days in the entire year. Which is better than a soothsayer I suppose.
But of course for you at home, there are ways of telling if the air and soil is warm enough and what the weather may bring for yourself. Buy a weather station. With a glance you can tell if the air has been chilled to uncomfortable levels overnight whilst you were tucked up in bed with Gardeners World. You can also have an inkling of what the weather is threatening to do with a barometer as your guide. If you are like me and become lost in the green world, a clock will help you realise supper was 2 hrs ago and perhaps the kids need feeding at some point.
In truth the UK has a fantastic array of weather and micro-climates from the abhorrently wet, to the surprisingly dry. Do yourself and your plants a favour and get a bit scientific.