Iceberg 4
ActiveLactuca sativa L. · Lettuce
GEBR BAKKER ZAADTEELT
Cultivation
Cultivation in open field conditions requires the selection of varieties adapted to uncontrolled environmental factors and climatic fluctuations. Such varieties are characterized by genetic plasticity, stress tolerance, and a vegetation period consistent with local weather conditions.
Mentioned in descriptions 28 305 varieties reference book.
Varieties for open field cultivation are bred for adaptation to uncontrolled environmental conditions, unlike greenhouse varieties. Their key feature is the ability to provide a stable yield under fluctuations in temperature, humidity, and light intensity, as well as increased resistance to regional disease pressure.
The choice of variety for open field cultivation depends on the phenological characteristics of the plant, where the life cycle must fit within the frost-free period of a specific location. Morphology is an important factor: preference is often given to determinate forms, resistant to wind stress, and the crop's ability to mature uniformly to facilitate harvesting.
Cultivation technology in open field conditions requires taking into account the biological characteristics of the variety, such as the need for insect pollination. Varieties for field conditions possess higher plasticity, which allows them to maintain yield under less intensive care and nutrient management, while greenhouse counterparts often demonstrate reduced productivity and susceptibility to stress under such conditions.
Selection based on the description text, not official resistance ratings: such data is not available in registers. Mention indicates that the trait is discussed in the variety's sources; see the variety's profile for details on what is specifically stated.
Lactuca sativa L. · Lettuce
GEBR BAKKER ZAADTEELT
Impatiens New Guinea Group · New Guinea Impatiens
Ludwig Kientzler
Tulipa L. · Tulip
KWEKERSVERENIGING PROMINENT 1
Verbena L. · Vervain
Mitchell Hanes
Viola x wittrockiana Gams · Garden pansy
Priscilla Grace Kerley, David William Kerley, Timothy Edward Kerley
Gladiolus L. · Gladiolus
Testcentrum voor Siergewassen B.V.
Rosa L. · Rose
Wilhelm Kordes,Tim-Hermann Kordes,Margarita Kordes
Begonia x hiemalis Fotsch · Elatior Begonia
LUBBERTUS H.KOPPE
Lavandula angustifolia Mill. · English lavender
Kerley Timothy Edward / Kerley Sarah Elisabeth / Kerley David William / Kerley Priscilla Grace
Rosa L. · Rose
Wilhelm Kordes,Tim-Hermann Kordes,Margarita Kordes
Dianthus barbatus L. · Sweet William
Brea Ezio (Impresa Individuale)
Alstroemeria L. · Alstroemeria
Konst Johannes Wilhelmus Maria
Alstroemeria L. · Alstroemeria
Konst Johannes Wilhelmus Maria|Nieuwveen, NL
Anemone hupehensis Lemoine · Japanese anemone
Jelle van den Haak
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Peter Rudolf Kolster
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Kolster Holding B.V.^^^Horteve Breeding B.V.
Gerbera L. · Gerbera
HilverdaFlorist B.V.
Rosa L. · Rose
Interplant Roses B.V
Echinacea purpurea (L.) Moench · Purple coneflower
TAKII EUROPE B V
Dianthus caryophyllus L. · Carnation
HilverdaKooij B.V
hybrids between Helleborus x ericsmithii B. Mathew and Helleborus x hybridus hort. ex Voss
Josef Heuger
Lilium L. · Lily
Vletter & Den Haan Beheer B.V
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Cornelis Pieter Eveleens
Viola x wittrockiana Gams · Garden pansy
Priscilla Grace Kerley, David William Kerley, Timothy Edward Kerley