John Pierce waxes exultant as he writes about what one can raise in a solar grower. That is what he calls a greenhouse that will grow food even in frigid weather by retaining the heat captured from the sun.
He lists plants from which one can make seasonings, teas, and tonics, and which are mature at under two feet in height (60 cm): basil, chervil, burnet, chamomile, chives, catnip, comfrey, garlic, marjoram, mint, nasturtium, oregano, parsley, rosemary, tarragon, and thyme.
One of the exciting things about the home solar garden, he says, is that you can ignore geography and have delightful tropical fruits right at home. Here are some of the types you can try, many of which he already has: oranges, lemon, lime, grapefruit and kumquat, as well as figs, grapes, kiwis, mangosteen, loquat , strawberries (a more temperate-zone fruit), and even bananas (yes, in a two-story grower). Of the last, he comments: ''I have had 100 pounds (45 kg) of fruit from a tree grown in a box 3 feet square, at 70-75 degrees F. (21 C. to 24 C.).''
No lightheaded romantic, this Mr. Pierce. He writes from Canada, where it can be mighty cold. He has built several solar greenhouses in Ontario and elsewhere.
He makes quite clear the differences between a traditional greenhouse and a solar space or solar grower. A regular greenhouse is difficult to heat in the winter unless steps are taken to insulate it. A solar grower, by contrast, conserves winter heat and can contribute warmth to a residence. The roof of the grower is insulated, often with the equivalent of 12 inches of fiberglass, as are both ends of the structure, the foundation two to four feet down, and sometimes the floor. Insulated double glazing also is used.
Pierce gives illustrated guides on how to build an attached or free-standing solar greenhouse. For those who may not have room, Pierce discourses on smaller devices, such as solar frames, pods, boxes, cloches, crop shelters, and balcony and rooftop solar gardens and window boxes.
Pierce discusses how to bounce light around with reflective surfaces to reach more plants, and where to use or obtain air blankets and other types of insulation at night.
''Growing Under Glass'' is a large-format paperback with spiral binder and clear plastic slipcase for use in the trenches. This book is replete with helpful plans for various kinds of sunspaces; though there is less emphasis on making use of the sun during the winter.
The volume, sponsored by England's Royal Horticultural Society and part of a series known as Simon and Schuster's Step-By-Step Encyclopedia of Practical Gardening, provides a thorough treatment of greenhouse practices, hygiene, pests and diseases, feeding and fertilizers, soil mixes, growing systems, plant support, pots and potting.
The two volumes together should give outdoor gardeners who want to take up gardening under glass plenty of food for thought and intelligent, informed action.