In February 2021, Winter Storm Uri changed how we build.

Queen palms (Syagrus romanzoffiana) came off every working list immediately; they are borderline zone 9b and had been marketed aggressively through the 2010s as reliable in north Texas. Japanese pittosporum (Pittosporum tobira) and its compact cultivars — routine screening shrubs in 2019 — lost their entire canopy and did not return from the root on most sites. Certain Podocarpus cultivars at immature caliper split at the branch union and failed to re-leaf. Pineapple guava (Feijoa sellowiana) froze back completely on exposed sites and recovered slowly, if at all. Borderline rosemary cultivars with proprietary trade names read as zone 8 on tag and performed as zone 9. None of these are specifiable for us now. We do not re-run the debate at the drawing stage.

Escarpment live oak (Quercus fusiformis) has become the default canopy species on drier western sites where it is naturally occurring, with southern live oak (Q. virginiana) reserved for moister eastern sites where its slightly less extreme cold tolerance still performs. Desert willow (Chilopsis linearis) replaces most of the tender flowering-tree register where the project calls for a lighter mid-story. Texas mountain laurel (Sophora secundiflora) is the reliable evergreen flowering specimen where a Mediterranean-adjacent register had once been assumed. For evergreen structure we lean into Juniperus virginiana eastern red cedar — native, reliably evergreen, indifferent to alkaline clay — rather than the imported Leyland cypress and Italian cypress that had been routine before Uri.

In the 72 hours after the first hard freeze of the season, we walk every project site where the planting is less than three years established. We document which species went fully dormant on cue, which showed partial canopy loss, which showed bark split or branch-union failure, and which simply failed. The observations are geotagged against the project record and against the microclimate reading made in the Site & Story phase — so a south-facing wall that modulated a freeze by five degrees shows in the record alongside the species that took advantage of it. Spring performance confirms or contradicts the January read. The documented cycle feeds the next project's Site & Story phase, which is how the palette continues to adjust rather than to recalcify.

Lueders limestone held at scale through Uri. Quarried roughly two hours west of Dallas, it is a dolomitic limestone with a dense, low-porosity grain that does not take on water in the same way as softer sedimentaries. Where we saw failure in DFW hardscape that winter was in imported sandstones — certain Pennsylvania-origin flagstone grades, Oklahoma sandstones cut too thin — spalling at the freeze-thaw interface and, on a handful of jobs, delaminating face-shell layers that had to be removed and replaced. Travertine in coping use, already on our do-not-default list for aesthetic and drainage reasons, performed predictably worst. Our current default has tightened: Lueders for structural hardscape, Pennsylvania bluestone where the register calls for a cooler tone and the thickness spec is right, and imported sandstones only on dry-laid path work where a cracked piece can be pulled and replaced without disturbing the whole field.

The pre-Uri DFW trade default ran cement-heavy and lime-poor, which produces a stiff mortar that cracks rather than flexes when the substrate moves under freeze. Our revised spec is a lime-rich Type N formulation calibrated for the freeze-thaw cycle, with an admixture package that we name on the terrace detail rather than assume the subcontractor will default to. Expansion joints are drawn at built-line dimension, not negotiated in the field. Strike pattern is documented: struck slightly concave at the face to shed water rather than trap it, consistent at every joint rather than varied by mason mood. We no longer accept “equivalent” as a mortar call from a subcontractor. The chemistry is on the drawing, and the drawing is what we sign off on before the first stone is set.

Autofill fittings, hose-bib housings, and electrical boxes at pool-deck grade: all three classes failed in Uri across DFW in ways we had not anticipated. The autofill we now specify is a brass-body fitting with freeze-break tolerance and a drain port — not the plastic-body economy fitting the trade had drifted toward. Hose-bib housings are frost-rated with integrated drain, not a standard sillcock wrapped in insulation. Pool-deck electrical is IP66-rated at minimum, with gasket replacement on a documented schedule rather than assumed to last the lifetime of the installation. We stopped accepting “close enough” from subcontractors on these three classes in 2021. The specification gets named by part number in the drawing set, and the installer signs off that the installed component matches.