Kaj je USDA zona?

Za enostaven prikaz informacije o prezimni trdnosti neke rastline vrtnarji delijo svet v zone glede na pričakovano minimalno zimsko temperaturo. Sistem je razvil Ameriški Oddelek za Agronomijo in je v začetku veljal le za Severno Ameriko, a je bil kasneje privzet za ves svet.

Vsaka zona pokrije območje 10°F, to je približno 5°C. Najhladnejša je zona 1, ki pokriva subarktična področja. Pod njo, v zoni 0, ni rastlin. Najvišja zona je zona 12, v njo spadajo ekvatrorialni tropi. Najnižja zona, ki je večinoma brez zmrzali je zona 10.

Vsaka rastlina ima minimalno in makssimalno zono v kateri bo preživela, in znotraj tega območje, kjer bo uspevala. Tudi vaši lokalni mikroklimatski pogoji so pomembni - preden se odločite za katerokoli rastlino prosim raziščite njene zahteve.

Te zone pokažejo le del klimatskih zahtev neke rastlinske vrste; razporeditev padavin, vetrovnost, povprečna temperatura po različnih mesecih, talni pH in mnogi drugi dejavniki igrajo pomembno vlogo. Na primer: mnoge rastline so zelo prezimo trdne, uspevale pa bodo le v območjih z vročimi in vlažnimi poletji. Mnogo kaktusov je prezimno trdnih - a le, če je njihov substrat pozimi popolnoma suh.

What is the USDA zone ?

For ease of conveying basic information about plants gardeners divide the world into zones according to expected minimum winter temperature. The system was developed by US Department of Agriculture and applied to North America only, but it has been extended to the rest of the world.

Each zone covers a range of 10°F, about 5°C. The coldest zone is zone 1, corresponding to subarctic climate. Below this, in zone 0, there is no plant life.The highest zone is zone 12 to which equatorial tropics belong. The lowest mostly frost free zone is zone 10.

Each plant has a minimum and a maximum zone in which it will survive and a range within this where it will thrive. Also your local microclimate plays a important part - before choosing any plant please research its needs.

These zones indicate only a part of the plant's climatic requirements; distribution of percipitation, winds, average temperature during different months, soil pH, and more - all play a role. For example: many plants are extremely frost hardy but will only grow well where summers are hot and humid. Many cacti are frost hardy, but only when kept bone-dry.