20 CIRCULAE NO. 113, BUREAU OF PLANT INDUSTRY. 



as runners. These should be set about 27 inches apart. Two rows 

 can then be planted with a garden drill between the furrows. Irri- 

 gation by flooding is also a common practice on this project, as well 

 as in other onion-growing sections. If this method of irrigation is 

 decided upon, the rows may all be the same distance apart. 



If the weather remains dry after planting, irrigation may be nec- 

 essary to germinate the seed. A tendency of the soil to bake over 

 the seeds indicates that irrigation is needed to soften the crust 



When furrow irrigation is used on soils that do not subirrigate well, 

 much slope to the land is to be avoided; otherwise the water may run 

 past without thoroughly wetting the soil about the plants. A slope 

 of 0.2 foot per 100 feet should give satisfactory results, and if the soil 

 is well supplied with humus more slope may be allowed, as such soil 

 takes water easily and washes less. The irrigation furrows shoidd 

 not exceed 300 feet in length. Often a field can be so arranged that 

 the water which runs from the ends of the furrows may be utilized on 

 a lower series. It is well to follow each irrigation as soon as practi- 

 cable with a wheel hoe, so that the growth of the onions will not be 

 checked by loss of soil moisture. Usually it is advisable to irrigate 

 every week or 10 days until August. 



The market requires thoroughly matured onions which will keep 

 well. To insure such, water should be withheld after the early part 

 of August and the soil allowed to dry out. The bulbs should mature 

 by September 15. A field full of scallions and immature bulbs 

 indicates either poor soil, poor seed, late planting, or too much 

 watering. 



Harvesting. — If the onions are properly matured, pulling is easy, 

 and two or three days' curing in the field will put them in good condi- 

 tion for the storehouse. It is entirely possible that it will be found 

 the best practice where onions are properly matured to top them and 

 put them at once into crates and store them in open sheds, where the 

 curing will take place without injury from night frosts or the hot 

 midday sun. 



Storing. — The important points in storage are dryness and low 



temperature. While a thin-board building, not frost proof, is better 



than a place too warm, a cheap adobe structure is especially adapted 



to this purpose, as any temperature in the fall or winter may be 



secured by regulation of the night ventilation, and the nonconductive 



adobe walls will prevent freezing. The bulbs can then be marketed 



at anv time. 1 



CELERY. 



Celery growing is not yet an important industry. This crop has 

 been very successful, and the produce is of excellent texture and 



! For further information in regard to onion culture, see Farmers' Bulletins 354, Onion culture, and 434, 

 The home production of onion seed and sets. 

 |( ir. 113] 



