Variety trials

Extremely high quality leeks are being produced on a small scale in the Willamette Valley with good yields. The crop is usually seeded in early spring, matures in autumn, and can be held through the winter for harvest the following spring. Very few varieties are grown commercially and the highest quality plants have been transplanted and grown in trench culture. The most lucrative market is the restaurant trade, which demands long, thick, blanched stems. Healthy foliage can also be used decoratively in presentation of restaurant dishes.

1. Varieties. Overwinter varieties must be winter-hardy and resistant to bolting after exposure to cold weather. They should be able to stand several months of light frosts and short periods as low as 0 ^oF. Bulb formation must start when daylength is between 10 and 13 hours. Storage quality is not of great importance since the crop should be marketed before the spring-seeded crop matures in September.

Methods

Methods

In northern states, spinach is normally planted in early spring for late spring harvest or in late summer for autumn harvest. Spring plantings are often limited by the difficulty of working cold, wet soils and many varieties bolt in the long daylengths and increasing temperatures of late spring. Autumn crops must be established during periods of very high soil temperature and low soil moisture and require frequent irrigation.

Overwintering varieties of cabbage are available, particularly from European seed companies. Variety trials were conducted in 1980 and 1981, with planting dates the same as for the cauliflower, but quality was low and disease incidence high. The hardiest varieties had pointed or conical heads which are not desired in the local markets.

From the Oregon Agricultural Experiment Station Special Report 769, April, 1986

Research report from OSU's North Willamette Agricultural Research and Extension Center

Delbert Hemphill
OSU Dept of Horticulture, NWREC

1. Varieties.
Winter cauliflower varieties require a cold period to induce head formation. The heads, or curd, of overwintering cauliflower are composed of true flower buds and are usually of lower density than for Snowball types in which the curd is floral primordia tissue. Stems often tend to be slightly green and flavor tends to be mild. Because of the low density and tendency to break up when the stem is removed, these varieties are considered more promising for fresh market than for processing.

This was the fourth and last of the series of variety trials and focused on mid-maturity varieties to determine those with the best combination of yield and quality. The previous trials had established that the best quality is obtained with varieties maturing in April and early May.

The trial was seeded on July 27, and transplanted on September 3, 1982. On February 16, 1983, 35 pounds N/acre as ammonium sulfate, 40 pounds N/acre as calcium nitrate, and 100 pounds/acre of 0-45-0 was sidedressed. An additional 75 pounds N/acre as ammonium nitrate was applied on March 14.