Orchard substrate covering is a common cultivation technique in dragon fruit production，playing a crucial role in soil moisture retention and fertility.Research on dragon fruit orchards in Hainan island indicates that diverse types of covering substrates are used in production bases，yet the impact of different substrate coverings on soil and dragon fruit growth remains unclear.Using red dragon fruit as the experimental material，this study investigated the effects of covering with eucalyptus bark，coconut coir，sheep manure，biochar，and a mixture of these four substrates on soil and aboveground growth in dragon fruit orchards.Results showed that all substrate covering treatments significantly increased dragon fruit yield compared to non-covering treatment.The cumulative yield during the experiment for non-covering treatment was only 1.21 kg/plant，while the highest yield was achieved with the mixture of four substrates，reaching 1.96 kg/plant，a 62% increase over the non-covering treatment.Eucalyptus bark，coconut coir，biochar，and sheep manure coverings increased yield by 25%，19%，32%，and 30%，respectively，compared to non-covering.The increase in dragon fruit yield was closely related to the number of flower buds forming fruit；the total number of flower buds for the mixture of four substrates was 69% higher than that for the non-covering treatment.Regarding soil，the mixture of four substrates significantly increased soil moisture content in the surface layer(0-15 cm)，showing a 103% increase compared to non-covering.Other substrate covering treatments ranked in terms of moisture content as follows:sheep manure>biochar>eucalyptus bark>coconut coir.During periods of high external temperatures，substrate covering significantly reduced soil temperature，with the surface temperature of the mixture of four substrates decreasing by 3.1℃ compared to non-covering.In terms of soil nutrients，the mixture of four substrates increased soil organic matter，alkaline nitrogen，and available phosphorus content by 35%，55% and 33%，respectively.Nutrient elements such as nitrogen，phosphorus，and potassium in dragon fruit plants and the weight of the root system were also significantly higher in the mixture of four substrates compared to non-covering.Cost and revenue calculations for substrate covering showed that the mixture of four substrates increased income by 93360 yuan per hectare compared to non-covering.In conclusion，the mixture of eucalyptus bark，coconut coir，sheep manure，and biochar substrate covering in dragon fruit orchards effectively increased soil moisture content，lowered surface soil temperature during periods of high heat，enhanced soil nutrient levels，and nutrient elements in plants such as nitrogen，phosphorus，and potassium，thereby promoting the increase of yield and profitability.