You can plant your beet seeds 3 weeks before your last frost date, and again about 2 weeks after the frost date for a second crop. Your seeding and spacing are somewhat dependent on how you plan on using your beets.
Philadelphia: Annual Weather Averages. July is the hottest month in Philadelphia with an average temperature of 26Â°C (79Â°F) and the coldest is January at 2Â°C (36Â°F) with the most daily sunshine hours at 10 in July. The wettest month is July with an average of 114mm of rain.
To find out how often it rises over 70, 80 or 90 Â°F each month in Philadelphia, scroll down farther. There are also monthly and yearly counts of days with cold weather. All the numbers are long-term historical averages based on climate data gathered from 1981 to 2010.