Ruud Kleinpaste: Growing tomatoes

Growing tomatoes is one of the big hobbies of New Zealanders, especially males!

It’s great to have a go at these fruit – there are many many varieties too and everybody has their favourite ones. But there are some problems that can occur, whether you’re raising them in an open garden bed, or in a tunnel house

Tomato – (potato) thrips are a nuisance; they got here a few decades ago and will attack Solanaceous plants (potatoes, tomatoes, nightshades, poroporo, and such weeds)

Tomato thrips adults and nymphs

I used to get heaps of them when growing tomatoes in Auckland, but in CHC they seem to be prevalent only in autumn (takes longer to develop plague proportions);

My best preventative action is to pull Solanum weeds out everywhere. It prevents them from settling on these hosts and survive during winter.

When you have a hassle: spray the plants with oil (Conqueror Oil or Neem Oil) on a regular basis (every 10 days or so); aim for the newer leaves/growth on the tomato plants.

Sprays with insecticides need to commence well before you see the first psyllids; it keeps their populations down too.

I generally don’t grow potatoes (only the early season varieties of potatoes (before Xmas)

Blossom End Rot on Tomatoes has always been translated as a deficiency of calcium. Apparently that is a myth in itself; it has more to do with the inability of the plant to transport calcium through the plant. Gibberellins appear to be playing an important role in that job and most NZ soils are not deficient in calcium; so: try some fertilisers with gibberellic acid (Seafood Soup/Seaweed Tea!)

Often the first tomatoes of the season show some Blossom End Rot. With settling temps and regular fertilisation/watering these symptoms often disappear.

Early Blight and Late Blight on stems and leaves can move pretty quickly through the plants.

Here comes the watering again!!! Only water the soil (NOT the leaves); remove the lower leaves as soon as practicable, so they don’t drag on the moist soil and get infected.

Underwatering also helps in this matter: keep the area drier; make sure the wind/air movement can dry the plants and stems quickly. If you have persistent hassles with blight: keep a regular fungicide treatment going

Passionvine hoppers (Scolypopa australis)

I call them fluffy bums – as their “nylon-filament tails” are prominent features

(of course these tails are made from fine waxy material!)

Photo / Supplied

They suck sap from a wide variety of host plants, often climbers (Wisteria, Passionfruit vines) and Perennials (salvia, Hydrangeas, Camellia, you name it!!)

Sap-sucking is their big impact on garden plants – sometimes they debilitate their host, pooping honeydew all over the place and that creates a deposit of sooty mould, like with some many sap-sucking insects in the garden

Slowly they grow larger and larger shedding skins along their journey (moulting), until they reach adulthood in summer: Moth-like insects with delta-shaped wings, showing prominent vein-markings; they, too, suck plant sap

These insects have the ability to jump quickly and far and the adult passionvine hoppers also flick and fly very smartly… avoiding the insecticides you may want to spray at them!!

They are impossible to spray with insecticides.

But the fluffy bums might still be reduced in numbers in spring, when they are still young:

On a wind-still morning, grab an aerosol can with simple fly spray and create an insecticidal mist around those densely-packed groupings of young and impressionable fluffybums; they may try to “jump away from danger”, but won’t be able to succeed.

LISTEN ABOVE

See omnystudio.com/listener for privacy information.