Dog Star Constallation

Dog Star nights Astro Bob

The “Dog Days” are the hottest, muggiest days of summer.  In the northern hemisphere, they usually fall between early July and early September. The actual dates vary greatly from region to region, depending on latitude and climate.  Life is so uncertain right now.  But, fall is coming.

In ancient times, when the night sky was not obscured by artificial lights, the Romans used the stars to keep track of the seasons. The brightest constellation, Canis Major (Large Dog), includes the “dog star”, Sirius. In the summer, Sirius used to rise and set with the sun, leading the ancient Romans to believe that it added heat to the sun. Although the period between July 3 and August 11 is typically the warmest period of the summer, the heat is not due to the added radiation from a far-away star, regardless of its brightness. The heat of summer is a direct result of the earth’s tilt.

Spending time outdoors this time of year is uncomfortable, potentially dangerous, due to the intense heat. However, the chinch bugs are very active in St. Augustine grass (for more information:, and the summer flowers need water.  So, take care of those tasks early in the day and then retreat to the air conditioning to plan your fall planting.

Plant tomato plants in August for fruit in October. Varieties such as Phoenix, Florida 91, Solar Set and Heat Wave II are good selections for setting fruit in high temperatures, should summer temperatures continue. Otherwise, try some of the newer UF/IFAS recommended varieties for fall planting in North Florida such as Bella Rosa, Tribute or Finishline.  For more information on tomato selection refer to:  For information on other vegetables for fall gardening refer to the Florida Vegetable Gardening Guide:

Many bedding plants flower quickly and can add color to the fall landscape. These include pentas, African marigolds, torenia, zinnias, melampodium and scaevola.  Other can be planted in October for blooms all

Hummingbird at Firespike flower

winter-long.  Plan spaces and color themes for calendulas, pansies, snapdragons and violas.  Add in ornamental cabbage or kale and some dusty miller to accent the garden.  They too will perform through the cold.  For more information on Annuals for the Florida Garden refer to:

Dependable fall blooming perennials include lion’s ear (Leonotis leonurus), pineapple sage (Salvia elegans), firebush (Hamelia patens), cigar plant (Cuphea micropetala), yellowbells (Tecoma stans) and firespike

(Odontonema strictum).  Also, garden mums (Chrysanthemum sp.) and many different Irises will add color again in the spring.  To gain information on perennials for Florida refer to:

Webster’s second definition of “dog days” is a period of stagnation or inactivity. But, even when the heat forces you to slow down on the labor-intensive work, there is plenty of gardening “activity” to do.  Stay in the air conditioning and plan that spectacular fall and winter yard.

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