Pretty soon, the sweltering, sun-drenched days of summer will be giving way to chilly fall days. Getting plants, pools and yards ready for the wrath of Jack Frost will be reappearing on many to-do lists. Test your soil ‘‘Our first recommendation is getting your soil tested,’’ said Tom Ford, director at Penn State Cooperative Extension Blair County. ‘‘That way you can bring the level of nutrients up to a level that is appropriate for your plants and crops.’’ Soil samples may be taken at any time of the year, but in planning for the next year’s growing season, fall is best, Ford said. Fall testing also allows you to take advantage of end-of-the-year sales, as well as plan for the upcoming spring. With soil, five things typically need to be tested, Ford said: pH (acidity versus alkalinity levels) and potash (impure potassium carbonate) concentration, as well as phosphorus, magnesium and calcium levels.