At best, a windmill palm can be coaxed to grow no more than 12 to 18 inches each year, rarely 20 inches.Click to see full answer. Also asked, how long do windmill palms take to grow?Large Windmill Palm’s typically over 8 foot, start to grow slowly. So, be cognizant of the growth rate of the Windmill Palm, before long (say a 3- 4 years) the palm might grow out of the planter and need to be either planted in a bigger planter or transplanted outside, to a foyer area, or open area.Likewise, how fast does a trachycarpus fortunei grow? It can grow at a rate of about a foot of trunk a year and despite what you may think about this tree it grows best in cooler weather and actually dislikes extreme heat. It can grow to 20 metres but it may take 60 to 70 years to reach its full height. Consequently, how tall do windmill palm trees get? A very slow- growing palm, Windmill Palm can reach 40 feet in height but is often seen much smaller, 10 to 20 feet tall. Windmill Palm works well as a framing tree, accent, specimen, patio or urn subject. It is ideal for use as an accent in a shady shrub border or by a front entryway.How do windmill palms grow? How to Make a Windmill Palm Grow Fast Remove all grass from around your windmill palm in a circle that is as wide as its canopy. Amend the soil around the palm. Spread wood mulch around the windmill palm where you removed the grass and added the soil amendments. Clear excess vegetation near your windmill palm.