Cultivation area of green asparagus increased in the recent years, as high nutritive value of green spears has been recognized. In Poland however the production of white spears prevails and it is still low. Asparagus is cultivated on light soils, but green spears may yield well on heavier, loamy soils as well. The aim of the study conducted in the years 1999–2007 was to assess the yield of green spears of asparagus cultivated on a medium heavy soil of loess origin. Plants of four asparagus cultivars of Dutch origin – 'Backlim', 'Gijnlim', 'Horlim' and 'Thielim' were compared in the experiment in the Lublin region. High total yield, affected by the year of harvest, but not by the cultivar was stated. Each year a significant (except the seventh year) yield increase was noted, only in the fifth year the yield decreased. Marketable yield of cv. 'Gijnlim' was significantly higher than that of the other cultivars. The mean share of marketable yield in the total yield was low, only 56,5% and varied very much with years (from 32.7% to 6.9%). The highest share of marketable yield in the total was stated for cv. 'Gijnlim' (60.4%), significantly lower (55.2–55.7%) for other cultivars. Plants of cv. 'Gijnlim' yielded significantly more spears in total and marketable yield than other cultivars. Marketable spears constituted on average 63% of all harvested shoots (the percentage did not differ between cultivars, but very much between years – from 30% in 2002 to 80% in 2007). The highest share of non marketable yield was stated in the years with a high rainfall deficit in May.

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