Corrections

Every data correction and clarification we have made, newest first. Typos are fixed quietly and noted in each page’s change log.

Last updated Oct 12, 2026

Corrections log

Corrections, newest first
DatePageWhat changed and whySeverity
Oct 13, 2026How long does grass seed take to growWe said most lawn grass seed germinates in 5 to 30 days. Our own cited University of Tennessee table gives 3–7 days for ryegrass, so the range is now 3 to 30 days in the intro, key takeaways and description.Data correction
Oct 13, 2026Should you rake leavesOur summary of the 2010 dandelion study now follows its abstract: the abstract does not say the earlier low-maintenance-turf work was Michigan State’s, and it links crabgrass to the 1.5-inch mowing height without reporting any effect of leaves.Clarification
Oct 13, 2026When to apply lime to lawnWe said a lawn on acid soil “can stay pale however much you fertilize”, which goes beyond our source. The page now uses Ohio State’s own wording: low pH can reduce color, vigor and recovery from heat, drought or traffic stress.Clarification
Oct 13, 2026How to winterize a hot tubJacuzzi’s deadline is to finish before nighttime temperatures drop below 32°F for consecutive nights; we had left out “for consecutive nights”. The page now quotes it and explains that our city tables use the first 32°F night because Hot Spring advises finishing before temperatures fall below freezing.Clarification
Oct 13, 2026How to winterize a hot tubHot Spring’s spring start-up dose is twice the normal amount of chlorine needed for superchlorination, to destroy the antifreeze. We had written “twice the usual dose”.Clarification
Oct 12, 2026Generator size calculatorOur FAQ on the “80% rule” now adds a related limit from a document the page already cites: Generac’s RG Protector spec sheet says average output over 24 hours shall not exceed 70% of the standby rating. The 80% rule itself is still a rule of thumb, not a manufacturer figure.Clarification
Oct 7, 2026Saltwater vs chlorine poolElectricity prices now use EIA’s January–July 2026 state averages (Table 5.6.B), the same table as our other energy guides, instead of July alone. The US average moved from 18.31¢ to 18.19¢ per kWh, so a gallon’s worth of salt-cell chlorine costs up to 56¢ (was 57¢); the state range is now 13.53¢ (Nevada) to 33.25¢ (California), and the city season costs in Table 3 moved by $0–5.Data correction
Oct 7, 2026What size generator to run a furnaceWe misstated Honda’s power-management example. Honda says a 3,000-watt generator runs the fridge, furnace, lights, TV and microwave easily, and that as little as 1,600 watts can work only if the furnace and fridge run at separate times and the lights and TV go off when either starts.Data correction
Oct 7, 2026When to apply grub controlWe said Texas A&M advises treating after the beetles’ mating flights end; it says the ideal time is around when grubs hatch or in their first few weeks. Kentucky’s product-timing details now say they come from its 2012 insecticide table, which Kentucky withdrew in March 2026.Clarification
Oct 7, 2026What temperature do pipes freezeWe attributed the 20°F figure in a Texas A&M AgriLife article to Joel Pigg; it is the article’s own wording, and Pigg advises precautions below freezing. The attribution is fixed.Clarification
Oct 7, 2026Fall vegetable garden planting datesWe implied the Piedmont Master Gardeners chose an early first-frost date on purpose. They give central Virginia’s average first frost as Oct 10–15 and use Oct 10 to be on the safe side; NOAA’s median for the nearest station is Oct 24, with Oct 10 as the 1-in-10 early date.Clarification
Oct 7, 2026When to apply winterizer fertilizerNew York’s rule against fertilizer on sidewalks was cited to a Cornell page that no longer contains it. It now cites the statute itself, Environmental Conservation Law § 17-2103; the rule as stated was correct.Clarification
Oct 7, 2026How much shock to add to a poolThe SLAM finish tests (combined chlorine 0.5 ppm or less, an overnight loss of 1 ppm or less, clear water) were cited to a Trouble Free Pool chart page that doesn’t contain them. They now cite Trouble Free Pool’s SLAM page; the tests are unchanged.Clarification
Oct 4, 2026Generator size calculatorBefore the calculator finished loading, its result box showed 7,500 running and 9,800 starting watts and recommended 8,000 W. With the default appliance list the calculator gives 3,920 running and 4,720 starting watts and recommends 5,000 W; the preloaded numbers now match.Data correction
Oct 4, 2026Frost dates by ZIP codeFixed a misquote: the University of Maryland calls the 10% date a “safer” planting date; the words “represents a safer planting date” were ours. The page also said the lookup showed hard-freeze dates and station elevation, which it did not; it now shows both, plus your USDA zone.Data correction
Oct 4, 2026When to close your pool“Thousands to emergency rooms each year” is now the CDC’s actual figure: nearly 5,000 emergency room visits in 2012. The leaf-fall advice is now worded as Anchor Industries gives it.Data correction
Oct 4, 2026Tankless vs tank water heaterAn FAQ gave Fargo’s February tap water as about 37°F; our data and Table 2 say 36°F. Added that the widely repeated 24–34% saving figure is attributed to a Department of Energy page that is no longer online.Data correction
Oct 4, 2026When to overseed your lawnA quote from a University of Illinois Extension release was attributed to a named specialist; the words are the release’s own and are now attributed to the Extension.Clarification
Oct 4, 2026When to fertilize your lawnMinnesota’s phosphorus rule now includes its exceptions (a soil test from the last three years, new turf in its first season); the Pinellas County rule now lists the National Weather Service watches and warnings it covers; New Jersey’s dates are worded as Rutgers gives them.Clarification
Oct 4, 2026When to aerate your lawn811 asks for a call “a few days in advance”, not “a few business days”; the link now goes to 811’s current site.Clarification
Oct 4, 2026When to plant tomatoesThe comparison said all extension dates agree with ours within about a week; Ohio State’s central Ohio date is 9 days later and Penn State’s 1–2 weeks, so it now says most do. Removed a reference to a commercial page we could no longer find.Clarification
Oct 4, 2026Frost vs freezeNWS Binghamton’s fixed end dates for frost and freeze alerts were described as current practice; the office describes them as an experimental program run in fall 2023.Clarification
Oct 4, 2026When to cover plants for frostThe note on when NWS Binghamton stops issuing frost alerts now says its fixed end dates were a fall-2023 test.Clarification
Oct 4, 2026Home page and section pagesRemoved wording that promised heating and cooling sizing tools and design temperatures, which we do not offer yet, and example numbers that did not come from our calculators. The seasonal calendar’s New Jersey fertilizer dates now match Rutgers.Clarification
Oct 3, 2026Pool volume calculatorA summary line said a straight-sided oval pool holds “about 12% more” than an ellipse. The correct statement: the ellipse formula comes out about 12% low (the oval holds about 13.7% more).Data correction
Oct 3, 2026Generator size calculatorRemoved a “typical range for homes like yours” line that had no source, and a surge duration of “1–3 seconds” that had no source. Appliance defaults now come from Champion Power Equipment’s published wattage chart.Data correction
Oct 3, 2026Pool salt calculatorRemoved an unsourced claim about test-strip accuracy and replaced it with Pentair’s published sensor accuracy (±500 ppm). Added Pentair’s 3,600 ppm target.Clarification
Oct 3, 2026Seasonal calendar (home page and section pages)Replaced task notes that had no source with points from our sourced guides.Clarification
Oct 3, 2026GlossaryRemoved the unsourced “1–3 seconds” from the definition of starting watts.Clarification

Severity levels

Typo: spelling or formatting, no change to meaning (change log only). Clarification: wording that could mislead or a claim we could not source. Data correction: a number, date, rate or formula was wrong.

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