Can on the same day that the vegetables are picked. Blanch in boiling water from 2 to 5 minutes. Remove, and plunge into cold water. Pack in sterilized jars. Add boiling water to fill the crevices. Add 1 level teaspoonful of salt to each quart. Place rubbers and covers in position.
Set the jars on the rack in the boiler and bring gradually to boiling heat. At the end of an hour's boiling, remove the jars from the boiler. Tighten the clamps or rims and set the jars aside to cool until the following day. Do not let the vegetables cool off in the boiler, as this results in over-cooking. On the second day, loosen the clamps or unscrew the rims, place the jars in warm water, heat again to boiling temperature, and boil for an hour; then remove them again. On the third day, repeat the hour's boiling, as on the preceding day.
Corn may be canned successfully in the same way.