Picking in the field calls for the closest care and supervision to prevent damage to the fruits and vines. Stems should be removed to avoid punching other fruits, and long finger-nails do great harm by cutting the skin and admitting infection. Containers should not be too large to be handled conveniently. Round half-bushel stave baskets and galvanized pails are excellent. Baskets made of quarter-inch staves rather than veneer are smooth and durable, but the investment is rather heavy unless dumping is resorted to. In practice, all sorts of boxes and crates are used, often the package that is used for marketing. No container as deep as a bushel basket should be used.
The stage of ripeness at which tomatoes are picked depends upon the time and distance to market. For home use or local market, fruit may range from the first turn to almost fully colored.
A few growers pick at the turn and use ripening rooms to prepare for local selling. In this way cracking, injury by soil, by insects, and by uneven coloring are avoided. Fruits are wiped and handled with less loss and may even be washed if need be.
Fully ripened fruit will not stand handling and hauling and will quickly deteriorate, reaching the consumer in bad condition.
For cannery, full ripening is desired with even coloring. MacGillivray[18] has shown that success in this is largely a matter of care in picking. Cracking and slight softening are not serious defects for this purpose, but molds and bacteria in broken places are serious as they throw the product out of grade or occasion rejection.
Picking Green
Most tomatoes for long distance shipment, are picked before color appears,—at the mature-green stage. One of the great difficulties is to judge this stage correctly; to train ordinary labor to pick by maturity and not by size. Immature-green tomatoes ripen slowly and do not achieve good appearance or table quality.
It is almost impossible to describe the ear marks of a mature-green tomato. Most of those usually cited are of doubtful value—glossy surface, whitish cast of color and the dark ring at the stem scar. The jelly-like or mucilaginous material in the seed cells has sufficiently developed in a mature green tomato so that the fruit may be sliced without cutting seeds. Of course, the tomato is ruined but the method can be used to check one's judgment based on the exterior. Also, one can learn by laying aside tomatoes judged mature-green and immature-green to ripen.
Some efforts have recently been made in Florida to pick tomatoes at the turn, that is, at the first show of color, a practice suggested by Sando[19] some years ago. This should provide fruits of uniform degree of maturity, that would be about ready to sell on arrival and it would eliminate the serious problem of immature-greens. It would require more frequent picking of fields and there could be no delay in packing. There would, doubtless, also be problems of temperature and ventilation in transit. Results of tests thus far have been rather encouraging.