Walking Iris plants are not at flowering age

I give my six-month-old plants liquid fertiliser every week and have observed new leaves sprouting, but no flowers. Is it normal for these plants to take such a long time to flower?

Cynthia Wong

Your Walking Iris (Neomarica) plants look very young and need a few more months to reach flowering age. They will not bloom until a stalk has at least 10 to 12 leaves.

They will also not flower if there is insufficient light; their current location beneath the tree canopy looks too dark. They need about six hours of filtered sunlight a day for robust growth, which can be supported with continued application of fertiliser.

Young plants could be holy basil

What are these plants? They started growing in my garden without my knowledge.

James Goh

The plants appear to be holy basil (Ocimum tenuiflorum). Rub the leaves gently; they should emit a spicy aroma. Check the area for any other holy basil plants, as this species readily produces seeds.

Nerve Plant may be waterlogged

I have a plant, but do not know its name. I water it every other day, but it is not doing well and keeps shedding leaves. What is wrong?

Jenni Lin

You have a Nerve Plant (Fittonia cultivar), which needs at least four hours of filtered sunlight daily and a well-draining growing mix.

It may be shedding leaves due to wet feet. Does its container have drainage holes at the base? If it does not, this can cause the growing mix to become waterlogged.

Ensure the plant is in a pot with drainage holes and incorporate perlite into the soil to improve aeration. Water it only when the soil feels slightly dry beneath the surface and do not let the plant dry out.

Propagate plants through stem cuttings

How do I propagate my cactus and vanilla plant? Also, how do I get them to flower or fruit?

Adrian Ling

Your cactus is likely the Golden Rat Tail Cactus (Cleistocactus winteri). This species may not flower in Singapore, as it requires a winter rest to trigger flowering.

To propagate this species, cut the long trailing stems into shorter sections. Give the cut ends time to dry and heal. Plant them in a gritty, well-draining growing mix and place them in a bright area to encourage rooting. Water lightly and periodically.

As for your vanilla plant, it grows as a vine and is easily propagated via stem cuttings as well. Cut a long stem into shorter sections and root them in a moist, porous mix in a bright but cool spot. The growing mix can comprise materials like sphagnum moss or coconut husk chips.

Your vanilla plant looks young. At this stage, it can be trained to grow on a wooden trellis that its aerial roots can cling to for support. In a few years, with sufficient space, it will be mature enough to flower.

Mature vines will need to hang off the trellis and undergo about two months of drought stress and cooler nights to initiate flowering. Hand pollination is required for fruit production.