CELEBRATING 28 YEARS! Welcome to My weekly series! THE LANDSCAPE ASK PROFESSIONAL ASK Linda K. Lillie of Sprigs & Twigs Linda K. Lillie has been President of Sprigs & Twigs, Inc. for the last 26 years. She is a graduate of Connecticut College in Botany, an accredited NOFA Organic Land Care Professional, a Connecticut Master Gardener and a national award winning landscape designer for her design and installation projects. Q: Hi Linda, We have two rhododendrons that have partially bloomed the past three years in late October/early November. The flowers do not fully display, but at least half the buds do start to open. The other rhododendrons around our house wait until spring to show their colors. Do you have any thoughts about what we are seeing? - Greg A: Hi Greg, There are two primary factors that affect plant growth and flowering; temperature and light. Many plants have day length 'switches' that determine when they grow leaves, vs. when they flower. Photoperiodism is the term used to describe a plants reaction to the relative lengths of daylight and darkness. In the past, scientists believed that daylight length determined whether a plant would form flowers, but over time, that proved untrue. Instead, it is the amount of uninterrupted darkness that determines the formation of flowers on most plants. A plant that requires longer periods of darkness is termed a "short day" (or long night) plant. These plants form flowers only when daylight is less than 12 hours and darkness is greater than 12 hours a day. Rhododendrons and many spring and fall flowering plants are short day (long night) plants. Your rhododendrons are blooming now in response to the increasing length of darkness, because it's similar to the conditions of spring (their usual bloom time). Many summer blooming flowers and vegetables are "long day" (short night) plants, blooming only when they receive less than 12 hours of darkness each day. Cold air and heavy frosts will stop the complete opening of the flowers. Any partially opened flowers will freeze this winter and fall off. They will not form new flower buds for next spring blooming. THESE ARTICLES ARE GOING DIGITAL! DON'T MISS OUT! USE THE QR CODE, OR SUBMIT QUESTIONS TO: Email: info@sprigsandtwigs.net, or Mail: Linda Lillie, Sprigs & Twigs Inc, PO Box 245, Gales Ferry, CT 06335 Sprigs & Twigs 860-235-0752 WWW.SPRIGSANDTWIGS.NET CELEBRATING 28 YEARS ! Welcome to My weekly series ! THE LANDSCAPE ASK PROFESSIONAL ASK Linda K. Lillie of Sprigs & Twigs Linda K. Lillie has been President of Sprigs & Twigs , Inc. for the last 26 years . She is a graduate of Connecticut College in Botany , an accredited NOFA Organic Land Care Professional , a Connecticut Master Gardener and a national award winning landscape designer for her design and installation projects . Q : Hi Linda , We have two rhododendrons that have partially bloomed the past three years in late October / early November . The flowers do not fully display , but at least half the buds do start to open . The other rhododendrons around our house wait until spring to show their colors . Do you have any thoughts about what we are seeing ? - Greg A : Hi Greg , There are two primary factors that affect plant growth and flowering ; temperature and light . Many plants have day length ' switches ' that determine when they grow leaves , vs. when they flower . Photoperiodism is the term used to describe a plants reaction to the relative lengths of daylight and darkness . In the past , scientists believed that daylight length determined whether a plant would form flowers , but over time , that proved untrue . Instead , it is the amount of uninterrupted darkness that determines the formation of flowers on most plants . A plant that requires longer periods of darkness is termed a " short day " ( or long night ) plant . These plants form flowers only when daylight is less than 12 hours and darkness is greater than 12 hours a day . Rhododendrons and many spring and fall flowering plants are short day ( long night ) plants . Your rhododendrons are blooming now in response to the increasing length of darkness , because it's similar to the conditions of spring ( their usual bloom time ) . Many summer blooming flowers and vegetables are " long day " ( short night ) plants , blooming only when they receive less than 12 hours of darkness each day . Cold air and heavy frosts will stop the complete opening of the flowers . Any partially opened flowers will freeze this winter and fall off . They will not form new flower buds for next spring blooming . THESE ARTICLES ARE GOING DIGITAL ! DON'T MISS OUT ! USE THE QR CODE , OR SUBMIT QUESTIONS TO : Email : info@sprigsandtwigs.net , or Mail : Linda Lillie , Sprigs & Twigs Inc , PO Box 245 , Gales Ferry , CT 06335 Sprigs & Twigs 860-235-0752 WWW.SPRIGSANDTWIGS.NET