Saturday, September 26, 2009

Repotting time

Following our spectacular dust storm on Wednesday, we almost had a replay this morning, with a second, but much milder dusty start to the day today. Fortunately it blew over and away fairly quickly, but the weather here has been windy and quite unpleasant all day, even though it's dry. Not good gardening weather, but reasonable repotting weather.

So I threw a tarpaulin over our timber outdoor entertaining table and presto! Instant repotting zone. My bromeliads have been begging for repotting for weeks now, and so they are first priority, but I noticed that my new native orchid was in a very, very dodgy looking potting mix, too, and a couple of other pots needed new mix. So there was plenty to do in this sheltered spot away from the gusty winds.

No, this person doesn't need repotting, but it is why I am repotting my bromeliads. I want more of this spectacular display. This shot was taken last November, when my variegated Neoregelia bromeliads were making babies. When they blush pink, you know the Barry White soundtrack is playing in the bromeliad garden.

Months later (ie, today), and mum (the red-tinged person on the right) wants her child (the yellow-green variegated large backpacker on the left) to leave!

Bromeliad babies are called pups, and the general rule of thumb seems to be that the pups need to be at least 30% the size of the parent before you cut them off and repot them. As you can see, this big puppy is about the same size as its parent, so it's well overdue for relocation to a new home. Apparently, sociologists say the same story is being repeated in human homes throughout the western world! Adult children still living with mum and dad...

Removed from the pot, you can see how the pup pops out from the base of the parent plant. What I plan to do is simply cut off the pups and repot them, and send the parents off to the green recycling bin, as I don't have space for that many pots. However, I have been told that if you repot the parent plant, it will probably also keep on growing and produce even more pups (although that isn't guaranteed – it's a bit hit and miss, I hear).

I just remove the pup from the parent with an old kitchen knife. Sometimes it goes well like this, and you get a little bunch of roots attached to the pup...

... And other times I stuff up and, while I think I'm making a precision surgical cut, I just end up with a stump like this. Having made this mistake in previous years I have found that both pups grow on nicely, so it doesn't seem to matter all that much. However, I guess a bromeliad expert might have something to offer on this topic, but I'm just a bromeliad newbie who likes them and has discovered that they're almost indestructible!

As for the the potting mix, I use a simple mix of equal parts ordinary potting mix and orchid potting mix. This has worked well for me for several years. I use my trusty purple scoop to measure out equal quanities, then mix together well in my handy trug. (Tip for inner-city gardeners: get a few plastic trugs – think of them as inner-city wheelbarrows.) This produces an ultra-free-draining potting mix, but it also helps to hold the almost rootless pups fairly securely, too.

Traaa daaa, four new bromeliads ready to go. The main thing with repotting pups is to make sure they are upright, not leaning over. My bromeliads live in a fairly shady but well-lit part of the garden, need almost no fertiliser, but they do like to have their central cup, which holds water, to be topped up if it hasn't rained lately. These are incredibly tough plants. The main method of killing them is over-watering, especially in winter. How they feed themselves is by leaf-litter falling and collecting in their water cups. The leaf litter breaks down, becomes plant food, and life goes on. If you like, you can give them very weak liquid feeds (half or quarter strength) once every now and then. However, I don't do this at all and they're healthy and happy, and have been for years.

At the recent Florafest Garden Festival I increased my native orchid collection by one extra plant, but I did spot a bit of pure white polystyrene poking out of the potting mix, and so I decided to investigate what lay inside its pot. Here's the result. El cheapo orchid potting mix, courtesy of chopped up polystyrene and a cheapskate plant breeder. Orchids aren't that fussy about what they grow in, but I just don't like polystyrene!

So, as I had the orchid potting mix out for repotting my broms, I treated the native orchids to a pot-full of real orchid potting mix. This is very, very free-draining, mostly composted bark.

Much better! A proper pot with proper potting mix.

As Pam bought a Lithops (aka living stone) at the garden festival, I was also suspicious about its planting medium, too. This turned out to be pure gravel – 100% tiny rocks, plus a bit of sand. That's probably not too far removed from a lithops' natural habitat, I guess. And at least there wasn't any polystyrene! But I repotted this little fellow into a 50:50 mix of grainy, shop-bought, succulent & cactus potting mix and the original tiny stones. Only time will tell if this works, but the blue-glazed pot is much better than the boring orange plastic original pot!

1 comment:

Lanie said...

After reading your blog about bromeliads, I started thinking about the need for some more flowers in my backyard (lots in the front but not back)...esp since it has a bit of a subtropical vibe going (with avocado, macadamia, ginger, bamboo etc). I am now cruising websites selling bromeliads and planning my next lot of puchases. Thanks.