Work on the heated wall had already started to John’s design. The plot was marked out and the foundations for the perimeter wall were already dug. The whole garden was to be walled with a double skin of deep red brick, and there were to be built three equally-spaced fireplaces, one above the other, where the charcoal burners could be lit and the smoke drift sideways through the wall till every brick was warm to the touch. The beds of the garden were not to be edged with box in the usual way. John wanted to raise them after a fashion never seen before. He wanted little brick walls to edge them, and the beds were to be filled with sifted earth and rotted manure. He even instituted a pile of manure from the stables, which was to be left to moulder and then turned over every month. ‘I don’t want it all fresh and carrying the roots of weeds into my garden,’ he explained to J and to the other vegetable gardeners. ‘I want the earth in these beds to be free of weeds and free of stones. I want this garden to have soil so rich and so soft that I could lay a strawberry plant on it and leave it to set its own roots. D’you understand?’

They grumbled behind his back but to his face they nodded and pulled their caps. John’s reputation as one of the greatest gardeners of the day had preceded him and it was an honour to work under him – raised beds, and stirred manure, hollow walls, or no.

The house was quiet after the festivities of Christmas; the duke had returned from the court in January and set up residence with Kate, his wife. His mother was to come later in the year. So Tradescant, rounding the stable yard in search of an errant weeding lad, was surprised to see an exceptionally fine horse, an Arab, being led from its stall into the yard, and the duke’s hunter prancing around on the cobbles, all tacked up and ready to go.

‘Whose horse is that?’ John asked a groom and received nothing more than a wink for a reply.

‘Dolt,’ John said shortly, picked up his hoe and went to pace out the orchard.

That afternoon, John was measuring the length of the new avenue which he planned to plant with lime trees leading from the Chelmsford road to the house when he heard hoofbeats on the drive and there were the two horses with two strange men on their backs.

John stepped forward to challenge them. ‘Who are you? And what’s your business here? That’s my lord’s horse.’

‘Let me pass, my John,’ said one of the men in a familiar voice. The stranger leaned down from the duke’s horse and swept off his hat. Buckingham’s dark eyes looked down at John, and John heard his irrepressible chuckle.