Landscape gardener and Life columnist Justin answers your questions.
I rescued some old-style gerberas from a house lot and have planted them wherever I have space - some under other shrubs, some backing on to brick walls and some in pots. They have survived their removal and have flowered but I have some mould and other problems. I have tried seasol spray and also baking soda (but not sure how often to do the baking soda and mix proportions) but it hasn't got rid of the problem. Also there appears to be a fluffy aphid-like infestation of flowering stalks.
Also, do they continually flower? Should I feed them more than something like the liquid seasol? I have just left them where planted but should I lift them?
- Helen Barrett
Gerberas like a free-draining, slightly rocky soil; they hate heavy soil and wet feet. They love full sun and will not flower as well in the shade. Make sure you keep them slightly moist and feed with a weak fertiliser like worm tea once every couple of weeks. To keep disease at bay remove dead leaves and flower heads. Healthy plants are able to deal adequately with pests but to keep aphids at bay, spray with soapy water or visit Kings for an alternative.Your plants will last three to four years but after that may need to be replaced.
Could you please give me your recipe for "baking powder spray" for mould on cucumbers, pumpkins and melons. Sounds like the magic potion I need.
- Brian
There are many versions of the baking soda spray - here is one. Don't forget this is a prophylactic spray and is best used in conjunction with other gardening methods such as companion planting and crop rotation. Make sure you spray under the foliage as well as on top, and remember, it's quite natural for many plants to deteriorate as the season wears on. No amount of spraying is going to change that.
Baking soda spray
Mix 1 Tbsp of baking soda and 1 Tbsp of vegetable oil
Add 2-4 litres of water
Add Tbsp of dishwashing liquid soap
Stir well
I have a passionfruit plant which does not have a lot of foilage on it but does have fruit in different stages of ripening. As the fruit ripens, it has patches of yellowish skin on it like large spots. Do I need to add some fertiliser to it, if so, what sort? I water it regularly every second or third day. The vine is about 2 years old.
- Diane McKenzie
Poor soil conditions are a real problem with passionfruit as they have a spreading, shallow root system. You may need to extend your mulch and compost out to at least a metre from the base of the plant. If the soil around the plant is heavy, over-watering may be an issue. Spray with Yates Copper and try not to water the foliage. Give the roots heaps of space and build up the soil layer with compost, but keep the trunk clear.
Weekend checklist
* To get big kumara tubers, prevent your vines from suckering on the ground.
* Keep pumpkins and other cucurbits well watered, taking care to avoid the foliage.
* Mulch and water everything. If you're lucky enough to get rain make suer you mulch your garden as soon as possible before the soil has time to dry out.
* Cover tomatoes and grapes with bird netting.
* Harvest onions after a few days of good dry weather.
* Plan now for your winter garden. Slow growers such as celery, parsnip and Brussel sprouts could be seeded.
* Sow beets and beans.
* Plant marigolds, petunias, asters, zinnias, Livingstone daisies and portulaca.
* Continue dead-heading plants that have finished flowering.
* Save seeds for next season.
* Let a few plants go to seed near desirables as pests are attracted to these weaker plants.
* Mow your lawn long and add the clippings to your compost as you turn it. Chop up any carbon or brown material really finely. This will accelerate decomposition.
