Can we plant out yet, please?

I went on a reassuring walk this week.  Feeling slightly guilty for my non-gardening housemate about the compost overflowing from every windowsill, I suddenly discovered a whole forest of plants crammed into bay windows on neighbouring streets.  Every other house overflowed with nasturtiums, sweet peas, lettuces and other annuals all bursting to get into the garden.  I could almost feel the anticipation.  But it made me wonder: when is it too early to plant out? 

The temptingly precise BBC garden calendar recommends waiting until 24 May to harden off tender bedding.  Most of my seed packets, a range of Wilkinsons own brand, Johnsons and B&Q own brand, suggest leaving it till ‘late May’. The Royal Horticultural Society, which obviously has Queenly connotations, says that to be on the safe side, one shouldn’t even think about planting out one’s tender plants before the date of the last frost, whenever that might be – and does add the caveat that the warmer the initial growing conditions, the longer the hardening off period.  Wise words

But most temptingly, Dan Pearson in the Observer says ‘do it now’!  So I did, but just with one lone Lupin which I thought strong enough to test theories on.  I was sadly wrong. My garden guinea pig got munched by mutant slugs within hours of being outside, then battered by a cool south-westerly.  Sheepishly I retrieved it from its freezing sunspot before total takeover, its little leaves depleted on one side, and its spirit gone.

Experiment aborted, I resolved for my poor Lupin to be the last plant I release before the 31^st. Roll on, June!