Trumpet vine may need fertilizer boost to flower
Look for a product with high phosphorus content to spur bloom growth
Q: We had a trumpet vine growing here for nearly 16 years at our home in the Foothills. The problem is it doesn’t flower nearly as well as many others we see in town. Is that due to out altitude or am I doing something wrong?
During its life I’ve tried cutting it back hard to barely trimming it some years to encourage more blossoms. It’s on a drip system and seems healthy other than not getting many flowers. Any thoughts for us? — J&J, Albuquerque
A: You don’t mention fertilization at all when talking about the trumpet. I think this creature could benefit from a “blooming” type of fertilization on a regular basis. “Bloom” maker fertilizers are higher in the phosphorus content.
On all fertilizer labels they list, always in this order, nitrogen-phosphorus-potassium as their chemical makeup. Remember this simple thought “Up, Down and All Around.”
Nitrogen makes green growth, the “up” in the thought. Phosphorus, the “down,” is used to create and maintain healthy root structures (and blooms). Then potassium, the “all around,” makes all the chemicals available by keeping cells within the plants healthy. That’s really simplified but it’s a great way to know which part of a fertilizer you need to get the results you want.
So if your flower-producing plants aren’t being as prolific as they could, they might just be “down,” lacking the mineral phosphorus. So with that, I believe it’s time to offer a bloom-booster type of fertilization. All wellstocked retail outlets should have a “bloom boost” style fertilizer available. Granular fertilizers are meant to be scratched into the soil surrounding the plant and then watered in to release the food and some are water soluble and can be sprayed directly on the plant itself along with being poured on the soil and absorbed that way.
Since it’s so remarkably hot you will want to be cautious if you decide to apply the fertilizer directly on the leaf surface. Please do that chore the very first thing in the morning, having it applied well before 7 a.m. Or better yet, much later in the afternoon, more like dusk so the plant won’t get scorched by the day’s sun!
Then I’d suggest that this fall after leaf drop you get out with a pitch fork and impale the soil around the area where the trumpet’s planted, being cautious not to stab or injure the plant roots. Then apply a stout layer of really well-aged manure. Be sure to water deeply at least monthly all through the autumn and winter months to get the manure working in the soil. This will get the soil more capable of water storage, mineral movement and oxygen holding so the trumpet might be more concerned with blooming as opposed to just having green growth.
I truly don’t think your altitude is affecting your trumpet’s lack of bloom, as I’ve seen them growing higher and completely awash with flowers! I’m hoping that it’s just hungry for more phosphorus in its diet and by getting it, that’ll solve the lack of flower that you are wanting, perhaps not his year but hopefully next.
Even though you don’t have blooms, you certainly have something growing green and lush, which is always a visual bonus in this place! Happy Diggin’ In!