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Question Topics This Month

Kumquat tree care QLD
Care of cyclamen NSW
Shrub for wet area NSW
Evergreen self-clinging creeper? VIC
Sweet peas dying QLD
Possums QLD
Fungus on canna NSW
Passionfruit vine from seed QLD
Sick port wine magnolia NSW

South-facing cottage garden VIC
Mandarin fruit drop SA
Small deciduous tree VIC
When to harvest potatoes VIC
To do this month? NSW
Can roses compete? NSW
Root systems of eucalypts TAS
Growing cumin NSW
Wisteria dieback VIC

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Topic and Question

Answer

Kumquat tree care QLD 

I have an ornamental Kumquat tree. I live in south east Queensland. The tree is in fruit now, when should I prune my tree? What pest product should I use to  keep my tree healthy?

BACK TO TOPICS

You don’t need to prune the tree at all but after the fruit is finished you can give it a light prune to shape if you like. You can use something like pyrethrum to control aphids and trim off any leaves badly affected by leaf miner (usually happens in early autumn – the leaves curl & look silvery.) You might also get a bit of scale that can be treated with white oil. The trees are pretty self sufficient – they just need regular wide watering and plenty of fertilizer in the growing season. Make some kumquat jam – it’s delicious!

BACK TO TOPICS

Don't overwater the plants or they will rot. Water them only if they are dry. Occasionally feed them with a water soluble liquid fertilizer or if they are in pots, dunk the entire pot in a bucket of diluted fertilizer for half an hour or so. Most importantly, don't keep them inside all the time. They are best kept outside on a deck or similar, or if you have them inside, pop them outside the door each night before going to bed.

Shrub for wet area NSW 

What type of shrub can I grow in a very wet part of my garden, which is also sunny. Water runs down from other properties which keeps it wet most of the time.

BACK TO TOPICS

You need a plant that grows naturally in boggy conditions. Some to try are Viminaria juncea (Golden Spray; Native Broom) - evergreen native shrub/ small weeping tree to 5m tall; fresh green almost leafless slender branches; yellow pea flowers in spring and summer,, best in full sun but will tolerate some shade, Banksia robur (Swamp Banksia) - native shrub to 2.5m; stiff foliage; greenish yellow candle flowers year round; full sun or semi-shade, Melaleuca ericifolia (Swamp Paper-bark) native shrub to 4m, tiny leaves, creamy flowers in spring; full sun or semi-shade.

Evergreen self-clinging creeper? VIC  

Is there such a thing as an evergreen Virginia creeper? I have a narrow drive and I need to cover an ugly south wall. Any other suggestions please?

BACK TO TOPICS

Virginian Creeper is deciduous as are others in the same genus. If you want a plant that will cling to the wall by itself then Creeping Fig (Ficus pumila) can look fantastic provided it's kept clipped close to the wall. If you are prepared to put up a support along the wall then Star Jasmine (Trachelospermum jasminoides) is a good choice.

Why are my seedlings dying? They are planted in a large pot with organic compost and have been fertilised with a fish based fertiliser. I have a metal trellis in the pot for them to climb up with string attached. The pot gets morning sun.

BACK TO TOPICS

Plant Sweet pea seeds into damp soil and then do not water them again until the seedlings emerge. Do not fertilise them at planting time. They extract nitrogen from the atmosphere and are only likely to need some additional fertilizer when they are in bud. If the established seedlings are dying it is probably caused by damping off - a fungal disease caused by the soil being too cold and damp. The plants need sun for most of the day. I'd be inclined to start again with some fresh potting mix.

Possums QLD 

We had a great crop of dwarf beans 6 months ago and when our latest climbing bean plants started growing and flowering-all in one night everything was eaten except the main tendrils. Even some tomato leaves and a small fruit were eaten. We have a mother possum and baby in the trees round here. Do you think the possums ate the beans plants? After half the plants were eaten one night I sprayed the plants with surface pest control thinking it could be insects/but next morning the residual plants were all gone. Our dog sleeps inside so maybe he would or could have saved them?

BACK TO TOPICS

I think it is highly likely that your resident possums are the culprits. If you want to grow vegetables you are probably going to have to devise some way of enclosing the plants in wire netting to keep the possums off. There is nothing that you can spray that is really effective in discouraging them though some things work with some possums. There are a few suggestions in our Garden Basics section http://www.global-garden.com.au/gardenbegin_techniques_2.htm#Dealing%20with%20Possums

Fungus on canna NSW 

I seem to have fungus, bright orange spots, growing on my canna plants.  I removed the damaged leaves, mostly from the base, in late summer but the new growth is showing the same disease. The cannas are planted beside a wooden fence and get very little northern light in winter.

BACK TO TOPICS

This certainly sounds like one of the rust fungal infections of which there are hundreds. Cannas are usually pretty free from disease attack. A location where there is better air-circulation would help. If you want to try a spray, then sulphur or zineb are worth a try.

Passionfruit vine from seed QLD 

I have a passion fruit vine that has grown naturally in amongst some trees/bushes.  I want to remove them but the vine will have to go too.  It would be a shame to lose the vine altogether so I've tried to grow some from the seeds but they keep going mouldy and horrible.  Can you grow them from the seed of the fruit?  If so how?

BACK TO TOPICS

It isn't worth trying to grow a passionfruit vine from seed. You will not end up with a vine like the parent plant and it will most probably be an inferior plant that grows like a weed and does not produce good fruit. You would be better off buying a new grafted plant that will give you good results.

Sick port wine magnolia NSW 

The leaves of my port wine magnolia are going yellow then brown and dropping off, no flowering. The plant doesn’t look good. Have tried giving more water, less water, fertiliser etc nothing is helping. It’s in a large pot on a balcony, has sun and shade.

BACK TO TOPICS

You need to have a good look at what is happening with the rootball and the best way to do that is to repot it. There is a possibility that the rootball has become water repellent and whatever you apply to it is not being absorbed. A wetting agent will help fix this. The plant could be pot bound. When you tip it out of the pot, check to see if the roots are coiled around inside. If so, prune the roots with a pair of clean, sharp secateurs and repot into a slightly larger pot with the best quality potting mix you can buy. You may even find something unexpected like an ants' nest in the pot.

South-facing cottage garden VIC 

We have had to redo our front garden after a liquidamber failed to deal with the drought and had to be removed. I need ideas for suitable plants - mixture of natives and exotics- that are drought tolerant for a front cottage style garden in eastern suburbs, Melbourne.

BACK TO TOPICS

You need to use drought-tolerant plants that will cope with little sun during the winter months. Deciduous plants will do this obviously. Camellias have proved themselves drought hardy and are always a good foundation for a cottage garden. Others you could consider are Correa reflexa, Crowea exalata, Philotheca jasminoides (previously Eriostemon), Viburnum opulus 'Sterile', Loropetalum chinense, Abelia x grandiflora, wormwood, coloured-leafed coprosmas. Choose a selection of different leaf colours and textures as well as flowering plants.

My mandarin tree is 6 years old.  Every year we always have plenty of fruit.  This year the fruit formed to golf ball size, then, bar 6, they all turned yellow and dropped off over a period of 3-4 weeks.  The tree is also losing lots of leaves at the same time. Help! Most of the damage was done when we had record heat wave conditions in Adelaide in early March.  We deep watered the tree every day so it could be that we may have overwatered or underwatered.  The drought conditions may have something to do with this problem.

BACK TO TOPICS

Fruit drop is typically caused by a change in watering regime. Your response to the hot weather may have been over the top. Try to water citrus consistently - no big increases or decreases in the amount applied. Put this event down to experience.

Small deciduous tree VIC 

I am interested in planting preferably, a native, deciduous tree that grows no more than 2-3 metres.  It will be placed in front of a north facing window and needs to be reasonably drought tolerant.  I haven't been successful in "Googling" the answer.  But I did think that a magnolia sp might do the trick, although I know it's not native.

BACK TO TOPICS

Choose an exotic deciduous tree instead. I don't think a magnolia is a good choice. It has a couple of weeks of glory in spring and looks very ordinary for the rest of the year. I'd go for one of the crepe myrtles in the Indian Summer range. They have great summer flowers, beaut autumn colour and the bare bark is very attractive in winter. Most grow to around 3-4m and there are a number of colours to choose from. Don't prune the tree - just let it develop its natural shape with just a tidy up of wayward branches if necessary. Pruning does encourage more flowers but I think it essentially spoils the tree.

Check them out at http://www.flemings.com.au/homegarden/indian_summer.asp?CULT_ID=IND10WEB

When to harvest potatoes VIC 

How do I know when potatoes are ready to be picked?

BACK TO TOPICS

Once the potato plants yellow off it is time to dig the spuds.

To do this month? NSW 

What needs pruning & planting this month? Also is there a recipe for spraying black scale on gardinas & keeping herbs from being eaten - organic please.

BACK TO TOPICS

Herbaceous perennials need to be cut down to the ground this month. They will be looking scruffy by now. Refer to the planting guides http://www.global-garden.com.au/ggplantguide.htm   for what to plant. Use white oil on the scale on the gardenia. Try garlic spray on your herbs to keep pests away.

Can roses compete? NSW 

I have a garden bed of 20m long and 4m wide, it is west facing, and has four big trees in the middle. I want to plant roses in the edge of the garden beds. My question is will my roses grow? The place receives 6hr sunlight everyday, and the trees are palm, bottlebrush, eucalyptus and wattle. If roses are not a good idea what will thrive in this condition.

BACK TO TOPICS

Roses don't like competition and the roots of these trees are quite fibrous and extensive so I don't think roses are a good choice. You need some tough little flowering shrubs to edge the bed that will give you colour and flowers over a long period. Keep them trimmed to the height that you want. Here are some suggestions: Nerium oleander, Abelia x grandiflora, Escallonia macrantha, Raphiolepis x delcourii, Rosemary, Weigela .

The root systems of large gum trees are very extensive and can certainly cause problems. However there are some lovely small eucalypts that you can grow that will be appreciated by the birds and should not pose problems in terms of height, limb sheer or root damage. Eucalyptus caesia spp. caesia (Gungurru) is an unusual and dramatic West Australian tree to 6m with pendulous branches. Eucalyptus leucoxylon ssp. megalocarpa usually grows from 5-8m tall, though may grow a little taller. It has bright pink to rosy red (and sometimes white) flowers - parrots and other native birds love them. Eucalyptus conferruminata (Bushy Yate) has fascinating sulphur yellow flowers and grows to about 9m. In Tassie, Eucalyptus niphophila (Snow Gum) might be more appropriate. It grows to just 4.5m.

Growing cumin NSW  

I was just wondering, is it possible to grow Cumin in Australia?  If it is - where can you buy the seeds or plants?

BACK TO TOPICS

Cumin grows best in Mediterranean-type climates. Read about it in our herb file at http://www.global-garden.com.au/gardenherbs2.htm#cumin

In Margaret Hibbert's Aussie Plant Finder, Honeysuckle Cottage Nursery is listed as a source of the plants in NSW. Here are the details:
Honeysuckle Cottage Nursery, Bowen Mtn, NSW
Ph 02-4572-1345

Wisteria dieback VIC 

My wisteria is approx 10yrs last winter/spring the buds formed and then just died!, so it never bloomed or did it produce leaves. when snapping off small branches they were hollow inside, thus my wisteria looked very dead. However it has started to sprout from the base again. Can I cut it back to the sprouting vines?. these vines would now be 6mths old. After pruning will I feed? Will this wisteria ever flower again? It faces the south side and grows on a brick fence.

BACK TO TOPICS

I have no idea what has happened to your wisteria plant. You have nothing to lose by giving it one last opportunity. Cut out and remove all the dead wood being careful to preserve the new basal shoots. Tie these up carefully to a support of some kind. If they are not bare already they will soon drop all their leaves. Leave the vine alone until August when you can fertilise it with a good all-purpose fertilizer, scattering the fertiliser widely around the plant. If you are lucky the new shoots will flower, if not, I'd probably remove the entire thing and plant another one elsewhere.

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