litchi tomatoes growing in Vienna. (by Barbara Damrosch)

If you had a day to spend in Vienna you might visit the paintings of Gustav Klimt and Egon Schiele in the city’s fine museums, then take in the grandeur of the Schönbrunn Palace, home of emperors. Or you might, as I did, spend a glorious afternoon at a small city farm on the grounds of said palace, fully absorbed by a bed of odd little fruits, all of them so close to the familiar garden tomato — and yet so far.

My guide was Wolfgang Palme, a tall, affable man of 40 who heads the department of vegetable growing at the Horticultural College and Research Institute at Schönbrunn.

Palme is an active figure in the conservation of edible-plant biodiversity in Europe, through his work with a major seed bank based in Austria named Arche Noah (Noah’s Ark), as well as his own trial gardens at Schönbrunn. His work puts him in partnership with other plant scientists as well as breeders, farmers, chefs, students, tourists like me and the children who take part in programs at the farm.

Palme and chef Johann Reisinger have organized Schönbrunn Seminars around a particular group of plants they grow and evaluate each year. It might be power herbs or superberries, or on my trip members of the nightshade family — the tomato, pepper, eggplant and potato clan. Obscure varieties are planted in trials and studied with an eye to improving their flavor and growability. The farm’s plots are near the exit to the Vienna Zoo, the world’s oldest. Families emerging are drawn into a plant world as engaging as the animal one they’ve just seen.

By late fall, when I visited, I’d missed the mysterious eggplant from Italy, so tender and juicy you could eat it like an apple. There were fallen tomatillos on the ground — those I knew. But mixed in were round, green-striped orbs the size of golf balls. “Tzimbalos,” Palme explained. “The skins are tough, but you can cut them in half and eat the inner part.”

A large plant with tiny yellow fruits caught my eye. “That’s Solanum abutiloides.” (Sometimes called dwarf tamarillo.) “It tastes sweet at first, then bitter.” Perhaps that one could be bettered by selecting the sweetest fruits, planting them and repeating the process year by year. Nearby was kangaroo apple with similar yellow fruit but beautiful purple flowers rather than white, eaten in southern Australia and New Zealand. Both are toxic unless fully ripe.

I got up the nerve to try a litchi tomato (Solanum sisymbriifolium). It looked very much like a red cherry tomato, but on a stiff plant armed with fierce prickles erupting from the stems, leaves and even the husk encasing the fruits. At full ripeness the fruits disengage easily, but not without pain for the picker (you’d want either tiny tongs or large tweezers). The flavor is intriguing, somewhere between a tomato and a grape. I’d make jam with them. I could also see this plant as a guard dog for the garden. Would any predator dare to breach a hedge of it? You can order its seeds from Baker Creek (Trade Winds Fruits also carries some of these Solanum delicacies-in-training), and because it has spread globally, you might even encounter it growing wild in a spot not far away and, hopefully, not in the dark.

Tip of the week

Pine trees shed old needles in the fall. Needle clusters closest to the trunk naturally turn yellow and fall in advance of fresh growth next spring. This is not a sign of distress. Fallen pine needles can be gathered and used as a light mulch. Keep them stored dry in leaf bags for use in next season’s vegetable garden. — Adrian Higgins

Damrosch’s latest book is “The Four Season Farm Gardener’s Cookbook.”