Growing and crafting gourds.
A hard-shelled gourd is the only crop most gardeners grow purely for the container it leaves behind. You plant it, feed it, give it a fence to climb, and at the end of it you get an object rather than a meal - a light, hollow, woody shell that has been used as a bottle, a bowl, a birdhouse and a musical instrument on every continent that could grow the plant.
It is a long game. The vine needs a full warm season, the fruit needs months of curing after that, and the whole thing looks like a disaster for most of the drying period. What comes out the other end is worth the wait, but nobody should start this expecting a result in the same year they had the idea.
Which gourds to grow
The craft gourds are Lagenaria siceraria, the bottle gourd, and they come in shapes named after what people made from them: birdhouse, bottle, dipper, canteen, kettle, snake. All are grown for the shell rather than the flesh. Luffa is the odd one out - Luffa aegyptiaca, a different genus, grown so the fibrous skeleton inside can be peeled out and used as a sponge. Ornamental gourds from the Cucurbita side are the small warty ones; they look good in a bowl for a season but the shell is too thin to work.
Growing and curing
Gourds want a long warm season, more than most temperate gardens give without a head start indoors, and a lot of room - the vines run ten metres and climb anything. Fruit is left on the vine until the stem browns and the shell stops giving under a thumbnail. Then comes the curing: months, not weeks, in an airy dry place with air moving all round. The skin goes mottled and mouldy on the outside, which alarms everybody the first time and is completely normal. A cured gourd is light, hard and rattles with loose seed.
Birdhouses
The birdhouse gourd is called that for a reason: hollowed, drilled and hung, it is the traditional nest box of the eastern United States, put up in clusters for purple martins for centuries before commercial boxes existed. The shell is thick enough to last several seasons outdoors if it is sealed, and the round shape sheds rain. Hole size decides which bird uses it, and the drainage holes in the base matter more than anything else you do to it.
Bowls, dippers and canteens
Cut across the middle a bottle gourd is two bowls; cut lengthwise down a dipper gourd it is a ladle with a handle already attached. This is the original kitchenware over most of the world and it still works - light, unbreakable, and free once you have grown the thing. Interiors are scraped out and sanded, and the shell is usually sealed inside if it will hold anything. The one honest limitation is that gourd vessels do not like sustained heat.
Rattles and instruments
A dried gourd with its own seed still loose inside is a rattle without any work at all, which is why gourd instruments turn up in nearly every musical tradition that had the plant. Beyond the shaker there are gourd drums, resonators for stringed instruments, and the West African kora and shekere, both built round a gourd body. The shell's hardness and its hollow shape do the acoustic work; the maker mostly decides how to hold it.
Carving, burning and dyeing
A cured shell takes decoration about as well as thin hardwood. It can be pyrographed, carved with a rotary tool, drilled into patterns that let light through for a lamp, stained with leather dye or ink, and polished with wax. The outer skin is scrubbed off first - soaking and a green scourer does it - and the surface underneath is smooth and pale. Dust from cutting and sanding gourds is an irritant and mould spores from the curing skin come off with it, so this part is done outdoors with a mask on.