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Abstract Wood ashes obtained from household heating and cooking are often applied to home gardens and arable fields by farmers. The effect of tree species and their locations on the elemental composition of wood ashes derived from domestic cooking and heating is unknown. The study aimed to discover the fertilizer values of wood ashes obtained from Betula pendula, Carpinus betulus, Fagus sylvatica, Larix decidua, Picea abies, Pinus sylvestris, Quercus robur, and Tilia cordata from two different localities, Hlinsko and Mšec, Czech Republic. The total element content in the ashes of dry wood samples (wood and bark) burnt at 460°C with a wood stove interfaced with a thermometer was determined using portable x‐ray spectrometry. The content (in g kg−1) of P (3.23–20.53), K (26.79–136.22), Ca (94.89–295.56), and S (2.97–11.75) in the ashes varies according to the tree species, locality, parent rock, and anthropogenic activities in the location of trees. Additionally, trace element contents ranged from 0.63–32.07 g Mn kg−1, 0.34–4.6 g Fe kg−1, 32.4–2062 mg Zn kg−1, 47.61–193.09 mg Cu kg−1, 3.99–21.53 mg Mo kg−1, and 1.50–6.62 mg Se kg−1. The pH of the ashes ranged from 8.71 to 11.54, suitable to alleviate soil acidity and a condition satisfying soil additive. A significant positive correlation between the contents of Cu, Sr, and Pb with the ashes of Picea abies, Larix decidua, Pinus sylvestris, and Betula pendula at Hlinsko is indicative of ancient anthropogenic activities input in the soil. The combustion of wood under home heating temperatures resulted in the concentration of most risk metal(loid)s, below permissible limits in agricultural soils. Application of wood ashes on arable fields requires considerable caution due to potentially toxic elements (Zn and Pb).

Excess potentially toxic elements (PTEs), including arsenic (As), cadmium (Cd), lead (Pb), and zinc (Zn), above permissible limits in the environment, have detrimental effects on trophic levels. Hence, imperative to devise advertent measures to address this situation, especially in the soil ecosystem: the major reservoir of many PTEs. Using aerial plant parts (shoot) to accumulate As, Cd, Pb, and Zn - hyperaccumulators are considered a permanent approach to PTE removal from soils. This communication expatiated the principles that govern the hyperaccumulation of plants growing on As, Cd, Pb, and Zn-contaminated soils. The contribution of soil microbial communities during hyperaccumulation is well-elaborated to support the preference for this remediation approach. The study confirms a flow direction involving PTE uptake–translocation–tolerance–detoxification by hyperaccumulators. Rhizosphere microbes exhibit a direct preference for specific hyperaccumulators, which is associated with root exudations, while the resultant formation of chelates and solubility of PTEs, with soil physicochemical properties, including pH and redox potential, promote uptake. Different compartments of plants possess specialized transporter proteins and gene expressions capable of influx and efflux of PTEs by hyperaccumulators. After PTE uptake, many hyperaccumulators undergo cellular secretion of chelates supported by enzymatic catalysis and high transport systems with the ability to form complexes as tolerance and detoxification mechanisms. The benefits of combining hyperaccumulators with beneficial microbes such as endophytes and other rhizosphere microbes for PTE removal from soils are vital in enhancing plant survival and growth, minimizing metal toxicity, and supplying nutrients. Inoculation of suitable rhizosphere microbes can promote efficient cleaning of PTEs contaminated sites utilizing hyperaccumulator plants.