The seed bank of native flora of the Botanical Garden - CZRB in Powsin was established in the early 1990s. Its establishment was associated with the increasingly pronounced negative changes occurring in the natural environment, resulting in the extinction of plant species, including in areas long protected (national parks, reserves). The seed bank in its concept is a complement to traditional methods of conservation in situ and creates a reserve in case of extinction of particular species in their natural sites. The bank's activities are a practical fulfillment of Poland's international obligations in the field of active nature protection ex situ (Convention on Biological Diversity, June 5, 1992).

Cryopreservation - preservation in liquid nitrogen at temperatures from -160°C to -196°C - was chosen as the method for long-term seed storage. Unlike the standard storage method used in most seed banks (storage at -20°C or ultra-drying of seeds), liquid nitrogen allows long-term storage of seeds (on the order of even several thousand years), without regeneration. This is due to the almost complete inhibition of aging processes at such low temperatures. This, in turn, makes it possible to protect samples from compromising their genetic stability and depleting the accumulated gene pool.

From 2001 to 2005, the seed bank's staff worked with mountain national parks, including the Kampinos National Park, which is adjacent to Warsaw. During this period, seeds of many rare and valuable Carpathian species were deposited in the bank (Dendranthema zawadzkii, Erysimum pieninicum, Pulsatilla slavica), as well as the peculiarities of KPN (Gentiana pneumonanthe, Succisella inflexa).

The seed bank participates in international and national projects. The ENSCONET (The European Native Seed Conservation Network) project was implemented in 2004-2009 in cooperation with 30 institutions from 18 countries. The result of the project was the establishment of a network of collections ex situ wild species, developing seed storage and germination methodologies. A virtual seed bank has been established with 48,443 objects, 276 of which are from Poland. In 2010-2013, the following were implemented project "Ex situ conservation of wild, endangered and protected plants in eastern Poland - FlorNaturOB"., as part of which seeds of 61 of Poland's rarest flora species were secured from 161 sites, and detailed documentation of the sites was prepared.

Currently, more than 730 samples of 220 rare, endangered and protected species of Polish flora are deposited in the seed bank. Seed viability checks and control of storage conditions are performed. The bank also conducts research in seed germination biology, chorology and flowering phenology of plants. It is also maintained database of stored seed samples.

Part of the seed bank is a greenhouse for acclimatization of seedlings obtained from germination tests.

Seeds deposited in the bank not only form a permanent genetic reserve, but can also be used to restore or strengthen declining populations.