This experiment focused on the production and evaluation of interspecies hybrids of Cucurbita (Cucurbita maxima × Cucurbita moschata) for use as rootstocks in cucurbit crops such as cantaloupe. The study involved cultivating and crossing various pumpkin and squash varieties under both controlled and field conditions, assessing germination viability and pollen fertility, and evaluating the morphological traits of the rootstocks. These evaluations were conducted over two years (2019 and 2020) at the research field and greenhouse of the University of Tehran, Iran. A total of 307 crosses were performed, of which 17 successfully formed fruit and produced seeds. The results indicated that characteristics such as hypocotyl length and diameter, germination percentage, and pollen fertility are critical factors influencing transplant success. Notably, the hybrids MB525×SI8910 and MB525×SB409 demonstrated strong performance in terms of morphological indices. For instance, MB525×SI8910 exhibited improvements of 44.26%, 22.22%, and 62.16% over the Takii rootstock in terms of hypocotyl length, diameter, and shoot dry matter, respectively. Although some hybrids showed high levels of pollen infertility, likely due to genetic incompatibility and environmental factors, several hybrids with favorable characteristics were identified. These hybrids show promise for use as commercial rootstocks. The observed traits suggest that producing well-adapted hybrids can enhance plant establishment under environmental stress and potentially increase both the yield and quality of horticultural crops. This research offers valuable insights into the application of interspecies hybrids in modern agriculture and underscores the need for future studies to focus on optimizing the genetic and environmental attributes of these rootstocks.