Giant Bird of Paradise Growth rate

[Palmfarmer]

I just planted one in my garden in open soil. I live in desert zone 9b. What can i expect in terms of growth rate? 

Edited September 25, 2020 by Palmfarmer

[Cedric]

Depends on how big it was when you grew it. Seedlings take quite an age but once they get a few meters tall and wide they rocket up forming trunks in no time. Birds disperse the seeds around for me so they pop up all over the place. In your climate it might be wise to create a micro climate as they rather like humidity and good summer rains with good drainage, dryish in winter. Sandy coastal moist but not boggy soil is prefered for fast growth. Take care with heavy sticky soil they don't love, the thick succulent roots rot easily.   Once a few meters tall and wide they will also start clumping. Def sub-tropical rather than tropical. I've never manged to get them to grow in South East Asia but in Africa they grow easily at the coast and even inland from the coast and at some altitude if given decent protection like a corner of a high wall.  If its too dry the leaves look terrible, too wet and it will keel over...from what i know about the zone system in the USA think 9a might be stretching it without very good protection.

Edited September 26, 2020 by Cedric

[Merlyn]

In Florida zone 9b/9a borderline my row of them grew from 2-3' tall clumps into 10-15' tall trunking monsters in ~2 years.  That's with 60-80" of rain and constant high humidity in the summer, so I am not sure about a more desert climate.  Mine are in relatively sandy soil, with not a large amount of organic material added.  They are definitely not in "muck" as Cedric mentioned.  Here's my row in the backyard right after I transplanted them 6 feet back towards the fence.  On the right side you can see the holes they were in, it's mostly coarse sand with some organics.

And before I moved them, you can see the size of ~2 year's worth of growth a bit better.  These were all below waist height when I planted them in early 2018.

[Estlander]

Here’s mine in Florida 9A. Planted in early spring 2018. I’d say they’re pretty fast. It’s getting ready to flower again for the 3rd time this year. 
The second pic is August 2018. 

Edited September 27, 2020 by Estlander

[Cedric]

Yah again it just depends on how big they are at planting. A nice clump with three or four shoots in sandy soil with humidity and warm is going to grow very fast. Little seedlings a few feet tall are much slower. Desert climate maybe not so fast. They do transplant very easily as non trunking clump. Be aware if you have a large clump of trunking Strelizia nicolai and you start trying to neaten them up a bit by removing shoots or trunks the entire thing can fall over backwards splayed out like a pile of matchsticks. They hold each other together.

Desert climate is a very different challenge. Protection and micro climate are the way to go. They can take a fair bit of cold in winter for short spells, right down to a couple of degrees Celsius but frost will make them look terrible if they survive........my Mum had some in her front garden at her retirement cottage (South facing Northern Hem) that thrived but the ones in her back garden (North Northern Hem) frosted to the ground. So they can take that cold with sunny days and a bit of warmth if you keep the frost off.

They make excellent compost. We put them through a shredder five meter trunks and all and pile up the shreddings under cover. Very nice open potting soil. Also a good way to get millions of seedlings as they germinate in the heap in no time. They can form pure stands at the expense of more worthy hardwood coastal tree species so are not in short supply

[Palmfarmer]

its a clump of 4 around 1.5 feet tall. unfortunatly the soil is on the clayish side there, but it drains good. They are planted right by my bananas to get some shade.

[Cikas]

They are very fast growing. Especially as older. 

[Merlyn]

On 9/30/2020 at 11:44 PM, Palmfarmer said:

its a clump of 4 around 1.5 feet tall. unfortunatly the soil is on the clayish side there, but it drains good. They are planted right by my bananas to get some shade.

At that size they will be fairly slow, mine picked up speed once they got to around 4-6 feet tall.  I think mine were around 2-3 feet when I planted them in the spring of 2018.  At 6 feet they started growing more offsets at the base.  I've cut off a couple of the offsets to spread them out a little bit, but mostly I just let the offsets grow as is.  I'll probably have to thin them out in a few years.  I realized that you could see my growth progression on my build thread here:

The July 18, 2019 posts show where I planted the row in April 2018.  The outer ones were about 2 feet tall, the two in the middle were 3-4 feet tall.  On page 2 the August 21, 2019 shows the original photo and then November 2018, then April 2019.  The white bird of paradise are getting close to 4-6 feet tall after 1 year in the ground, since the fence in the photo is a 6 footer.  By June 2019 they are 4-7 feet, depending on the spot.  The photos near the bottom of page 3 are the same that I posted above.