How to revive newly planted Phormium?

[RobNewtown]

Hi - I bought two of these about 6 weeks ago at Bunnings. They were bright and beautiful.

i planted them in pots with drainage at bottom, new soil and some mulch. Location faces NE, dappled sun to 1pm or so and quite light.

However, they are dying - loss of vibrant colours, flaccid hanging leaves eventually turning brown (which I cut off). Last week I completely took them out, examined roots (seemed ok), thoroughly  turned over the soil and replanted. But - so far no good.

I’m wondering about overwatering vs under-watering? I’ve read conflicting advice, esp when these are small. Also, I fertilised once with seaweed extract (diluted as per instructions on bottle).Maybe this was wrong?

Im stumped, esp as I expected these would be hardy and easy to grow. Any advice please? 🙏 

 

Photos - Before and now.

[MitchellMc]

Hi @RobNewtown,

Watering is often the main culprit in potted plants. Even though the soil looks dry right now, that could just be because you haven’t watered in the last couple of days. What’s important is the overall watering routine. For Phormium in a pot, you want to keep the soil consistently moist but not soggy. Water thoroughly when the top couple of centimetres of soil start to feel dry, and then let any excess drain out. Having drainage holes in the bottom of the pots is essential; without them, water can sit around the roots and cause rot.

Generally, in warmer weather, you might be watering every few days, but in cooler weather, it could be once a week. Mulch on top helps retain some moisture, but don’t let it keep the soil too wet. With small plants in pots, it’s very easy to overwater or underwater because the soil dries and wets faster than in the ground. Keep an eye on the leaves; if they start flopping and browning, it’s usually a sign to adjust your watering up or down. 

Please let me know if you have any questions.

Mitchell

[RobNewtown]

Thanks, Mitchell!
I forgot to mention that, 3-4 weeks ago I noticed brownish powdery residue over the leaves. I wiped off manually as much as possible and gave a spray with Yates fungus gun (thinking maybe powdery mildew…? No signs of mealy bugs I thought). The powdery stuff still seems gone now but plants aren’t good. Any ideas on this pls? Very limp.

When I pulled them out a week ago the rootball soil was quite damp (not soaked). Pots are well drained and I have been watering quite moderately 1-2 x pw. But maybe still too damp.

[MitchellMc]

It sounds like the main issue is likely drainage and watering frequency @RobNewtown. If your soil is still quite damp even when watering only 1–2 times per week, it suggests water isn’t moving through the pot efficiently. Ideally, you want to water so the soil is fully saturated and excess water drains out through the bottom holes over the next day or two. The top of the soil should start to dry after a couple of days, while the base remains damp.

In late spring or summer, once-per-week watering is usually too little for potted Phormiums. Depending on pot size and weather, watering every 2–3 days may be necessary, but only if the soil drains well and doesn’t stay soggy. Can you tell me how many drainage holes your pots have? Even a well-draining pot needs multiple holes so excess water can escape. Right now, the limp, struggling look could be from either waterlogging or inconsistent moisture, so improving drainage and increasing watering frequency should help the plants recover.

I'm uncertain whether the residue has anything to do with the current health of the plant. However, I can tell that the plant's soil is bone dry on top and in desperate need of watering. If the soil further down is still soggy/damp it points to drainage as the main culprit.

Mitchell