4 BULLETIN 797, U, S. DEPARTMENT OF AGRICl'LTUEE. 



than on heavy soils. The character of the bulbs grown on heavy and 

 on light soils will vary somewhat, of course, as it will with shallow 

 and with deep planting. The indications are that success can be 

 secured in bulb production on a friable loam soil, whether it has a 

 preponderance of sand in its composition or not. 



TEMPERATURE, SOIL, AND FERTILITY REQUIREMENTS. 



We may gain a valuable lesson as to the requirements and suit- 

 ability of these bulbs from the long private experiences of those who 

 have flowered them either in pots or in borders in different regions 

 and then tried to carry on their propagation. It is the common 

 experience that these stocks gradually deteriorate in size in the hands 

 of the small grower. This is not always a proof of lack of adapt- 

 ability, because it is seldom that the stocks are properly handled. 

 They become overgrown with weeds, are left undug too long, or are 

 improperly, fertilized. 



About 40 miles from the coast in northern California we have a 

 record of an apparent intelligent handling of Darwin tulips over a 

 period of years. Here, with good fertility and proper handling, the 

 bulbs gradually deteriorate in size. Two natural conditions in this 

 locality seem to be accountable. The moisture is likely to fail sud- 

 denly before the plants complete their growth, and the temperatures 

 are likely to run suddenly high at the same time, thus shortening the 

 growing period suddenly. Such conditions are evidently not suited 

 to commercial bulb production. 



The consensus of experience in the vicinity of the District of 

 Columbia probably would be very similar to that in the interior 

 region of northern California — the bulbs gradually deteriorate in 

 size. In this region, however, the average soil is naturally poor, 

 which, coupled with imperfect growing of small lots, is responsible 

 for much of the failure. There has been recently ample proof that 

 all of the robust varieties of both the nacissus and the tulip can 

 be successfully produced in good quality even here. It is not to be 

 considered, however, that the conditions are by any means ideal. 

 The main adverse condition, aside from natural lack of soil fer- 

 tility, is the high temperatures, which are normal for May and June 

 and occasionally occur even in April. There is also an uncertainty 

 regarding moisture supply before the end of the growing season. 



Suitable temperature, moisture, and soil conditions obtain in both 

 our Atlantic and Pacific coast regions. In the interior of the eastern 

 United States, as far west as Illinois and Michigan at least, condi- 

 tions are favorable enough for success. The temperature is not as 

 favorable as in the cooler coastal climate, but, in our opinion, where 

 friable well-drained soils occur the conditions are generally as satis- 



