I’ve spent many a long spring day sprawled beneath the trees of the Oxford University Botanical Gardens, and I’m not alone. The garden’s lush herbaceous borders, cool grass and green shade offer a compelling place to rest in those first warm afternoons of the season. But, to my mind, the place is never more beautiful than during the frosty mornings of deep midwinter. Outside in the still and empty gardens you can hear nothing but the crunch of the frozen ground underfoot. You can seek refuge from the cold in the various rooms of the Hot Houses: there is the citrus room, with its bright oranges and lemons that smell like Italy in the summer; the fern room where you can trace the fractal patterns of the leaves with your fingertips; the palm room where you can wander the curving pathways around the tall trees; the pond room where you can trail your fingers over water lilies and look at the bright carnivorous plants, hanging down on waxy, sappy tendrils; or the arid cactus room, where this Texan always found a little taste of home when she was missing it most.