Stewarts at Broomhill has positioned a Mini car outside surrounded by British-grown plants.
Stewarts retail and marketing head Terry Head said: "We are reminding visitors to consider patriotic planting. This year we have made a focused effort to fill our two centres with beautiful plants cultivated by British nurseries. Over 90 per cent of our stock will be sourced as locally, including over 11 per cent being supplied by our own nursery here at Broomhill."
He added that the garden centres were trying to use as much local produce as possible. They are a preferred supplier for the New Foest mark and this has grown into local plants too.
He said Stewarts only have two Dutch suppliers, including one for houseplants and that the proportion of homegrown plants sold was growing.
Head said most shrubs and herbaceous stock came from it own nursery.
Stewarts grows 1.5 litre and 2.5 litre shrubs including Aucuba, Berberis, Buddleia, Ceanothus, Choisya, Cistus, Cordyline, Cotoneaster, Escallonia, Euonymus, Fuchsia, Lavandula, Phormium, Potentilla, Spirea, Viburnum and Weigela as well as perennials such as Acanthus, Agapanthus, Ajuga, Aquilegia, Aster, Astrantia, Bergenia, Brunnera, Campanula, Coreopsis, Dahlia, Delphinium, Dicentra, Digitalis, Echinacea, Euphorbia, Gaura, Geranium, Geum, Helenium, Helleborus, Hemerocallis, Heuchera, Hosta, Leucanthemum, Lupinus, Nepeta, Papaver, Penstemon, Phlox, Primula, Rudbeckia, Salvia, Sedum, Thalictrum, Verbascum and Verbena and grasses Acorus, Carex, Cortaderia, Festuca, Hakonechloa, Imperata, Miscanthus, Ophiopogon, Panicum, Pennisetum and Stipa.