e-mail Jane Owen with your gardening questions: jane.owen1@timesonline.co.uk

None of the five giant pumpkin seeds I sowed have come up. They cost a lot. I sowed them directly into the compost heap which would give them the best start. That was six weeks ago. Nothing. Martha Grant, Nottingham

I have never sowed directly into the ground, partly because pumpkin seed is expensive (although, I now use my own from the previous year) and partly because they like a good burst of consistent heat to get off to a good start before being hardened and planted out. It may be that your compost heap was not sufficiently hot, or more likely, the seeds have been eaten by mice, rats or birds! It isn’t too late to sow another lot of seed – in the safety of an airing cupboard this time.

Some neighbour has a garden full of what my aunt used to call ‘mind your own business.’ It's a small, ground-hugging, very ‘spready’ weed, which has crept into the lawns. Is there anything that I can do to get rid of it? Many thanks in anticipation. Yours sincerely, Jill A Johnston

What have you got against mind-your-own-business or Soleirolia soleirolii? It is a wonderful plant – its pale green evergreen foliage makes a brilliant alternative to lawns, because it will grow in challenging conditions including shade. Plus, it is low maintenance. I am currently trying to encourage some to grow in the cracks of my paving, and so, if you really have taken against this plant, you could start by sending me some of it! More seriously, once established, it can be difficult to eradicate. You could use a herbicide like glyphosate, but it may be difficult to apply without affecting neighbouring plants – so you’ll have to keep digging it out.

And once you have, what then? You may find it difficult to establish anything much in its place. If it has seeped into the lawn, that is because growing conditions are better for mind-your-own-business than for grass. Therefore, unless you strip the lawn back, add some drainage and some new topsoil and remove any shading in the area, you may find that mind-your-own-business, or moss, creeps back into the space left behind.

Dear Jane, I have two green cordylines, one recently planted in multi-purpose compost in a large urn, and one in the ground, about two-years-old. Both plants are losing colour and turning a pale green/yellowish colour. I have fed them with Growmore and liquid and with plant food and iron but with no improvement I also have two skimmia in the ground experiencing the same problem. Please can you help? Honor Niland

Well, at least the plants aren’t suffering from mineral deficiency, but without knowing more about the symptoms, this yellowing could be caused by any number of problems: over or underwatering or red spider mite. Red spider mite is usually only a problem under glass, but it will attack outside under certain conditions and in warmer parts of the country. Have a look at the leaves with a magnifying glass and see if you can spot fine webbing and tiny, yellow-y insects (their name comes from the fact that they turn red/brown in late summer). For future reference, hosing down the plants regularly will usually prevent an infestation, but if this is what your plants have, the infestation must be extreme by now and will need radical action. There are predator controls, but at this time of year when temperatures are unpredictable, they may not work (yes, the predators can work outside as well as under glass, so long as the conditions are OK.) Instead you should spray regularly with bifenthrin, or a ‘green’ alternative like fatty acids, until the infestation has cleared up on all your plants.

Dear Jane, I have a north-facing garage wall and would like a climber that is not too vigorous - to grow only 6 to 8 feet. I had a honeysuckle but it grew too much and didn't flower hardly at all. I think it was Henrii and evergreen but boring. Any suggestions, ideally for something that flowers? The wall is in the shade 24/7, as the garage is behind the house. Best wishes, Chris Wood

Some of the climbing hydrangeas will work in the position you describe, and although they tend to be on the vigorous side, they respond well to being cut back. The evergreen clematis armandii is also vigorous, but it can usually cope with shade – and you will have to chop it back. Escallonia and Euonymus ‘Silver Queen’ would do OK, and if you want a honeysuckle, try Lonicera japonica ‘Aureoreticulata.’ Finally it’s hardly a climber but you could train flowering current in the position you describe.

Hi Jane! I have been trying to grow vines in pots outside for the past three years - plenty of growth and leaves but no fruit. This year is different though - I seem to have fruit starting to show everywhere. Can you tell me please, do I leave it all alone or do I prune some? If so, where do I start? Thanks, Graham, Wolverhampton

It’s pretty normal for vines to take a while to produce fruit. Now that the fruit has appeared, you will probably need to thin each of the bunches. This means cutting out up to 50 percent of the fruit to give the rest space to develop. Thinning also ensures good air circulation, which in turn prevents disease. As the grapes swell, the bunches may need to be thinned again later in the season. I assume you’re training the vines as standards - the best method for container-grown vines. This means that when the plant is completely dormant in mid-winter, you take out all but four or five shoots and then stop those shoots at six leaves.

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