Bulliform‐enriched tissues have increased cuticular conductance rates. Cuticular conductance, representing rates of water loss across the cuticle in the dark when stomata are closed, was measured during dehydration of detached leaves (20–22°C, 55%–65% humidity). (a) Cuticular conductance for three BC‐enriched mutants wty2, dek1‐D, and Xcl1 and corresponding wild‐types). CC rate is calculated as water loss (g) per hour per g dry weight (DW). Values are given as means + SD (n = 3–5 biological replicates per genotype). Statistical analysis used two‐tailed unpaired Student's t‐test, with ***p < .001. (b) Cuticular conductance rate of adaxial and abaxial leaf surfaces (one‐sided dehydration was achieved by covering one side of the leaf with petroleum jelly) compared to full CC rate, calculated as water loss (g) per hour per g starting weight (SW). Values are given as means + SD (n = 5–6 biological replicates per surface). Statistical analysis used 1‐way ANOVA, means with the same letter are not significantly different from each other; Tukey's post‐test, p < .05