Ask the Expert

Hi there, I planted mint in my garden a while back but now it’s sprouting up all over the place. I keep pulling it out but it’s taking over the garden, what can I do?

Posted 18/08/2015 by Phyllis, Dublin

Hello Phyllis, Mint is a sneaky plant, and it spreads all over the place by underground runners. So, I’m afraid that it’s a case of the horse having already bolted. The only way to get rid of it is to dig it up, or to treat it with weedkiller. In future, grow mint only in containers, or where you don’t mind it spreading. Mint is happy in shade, and is useful for colonising neglected patches.

Hi, I sowed rhubarb from seed a few years ago and it has grown very well except it is very green and bitter. The variety was called champagne and on the packet it looked extremely red which is what I like. Is there any way to make it redder? Thanks,

Posted 17/08/2015 by Terry, Carlow

Hello Terry, ‘Champagne’ rhubarb has very red stems, and good, deep flavour. As with all rhubarb, it should be grown in full sun, in very fertile soil, and with plenty of moisture. Seed-raised rhubarb is not always reliable, and it sounds as if you have been unlucky. Painful as it is, I think you might be best cutting your losses and seeking out some new rhubarb plants, either from a friend or from a retailer.

Is there a way of getting rid of bindweed?

Posted 21/07/2015 by Angela, Co Wicklow

Bindweed is one of the most persistent weeds, and if there were an easy, reliable way of getting rid of it, someone would be very rich today! In my experience, it is almost impossible to completely eradicate it, and you can hope only to control it. Here are a few methods that you can try. 1. Cover the whole area with carpet or other weed-suppressing material for at least a year, so that lack of light eventually kills off the roots. Be careful of shoots running out from the edges of the covering. 2. Carefully dig over the infested area, and remove the white roots. If you can then leave the area for a few months over the growing season, the roots you missed will resprout, and you can go at it again. 3. Spray off the entire area with weedkiller, leave for a few months, and spray off again when new growth has appeared and is growing strongly. If you use a weedkiller, wear protective gloves and eyewear, and follow the instructions on the packaging carefully. Note that bindweed wilts naturally in autumn, and there will be no regrowth until spring. Weedkillers work best in spring and summer when growth is strong. 4. If you cannot start with a clean bed, that is, if there are shrubs or perennials that cannot be moved, then you can spot-treat the bindweed. Stick bamboo canes into the ground so that the bindweed twines up them, and when there is good growth, brush on weedkiller, but be careful not to get it on the surrounding plants. You may need to do this over a period of two or three years. 5. Use any of the methods above, combined.

In the autumn, can I cut back hard my lavender plants - back to the woody branches?

Posted 20/07/2015 by Angela, Co Wicklow

Unfortunately lavender does not usually regenerate from woody branches. If the plants have become old and straggly, it is best to replace them with new ones in spring. Pruning is best undertaken in late summer, when the plants have finished flowering. Don’t cut back to the wood. Instead, cut off the old flower stalks and a further one or two inches of this year’s green growth.

I have only had a poor crop of thin and weak rhubarb. It is growing in a container that is 14" wide x 16" deep. Please can you advise do I need to replant?

Posted 10/07/2015 by Rosie, Wales

Hello Rosie, I’m afraid that rhubarb is one of those crops that prefers to grow in the ground. Relative to other plants, rhubarb produces an enormous quantity of foliage and thick, juicy stalks, so it needs to feed and drink accordingly. It also has a large root system that helps it to find and store enough nutrients and moisture to support all this growth. The best option would be to replant it in the ground with some farmyard manure added to the hole. If you have to keep it in the container, you could repot it into a John Innes number 3 compost. Water it well after planting, and make sure that the compost is kept moist for the next couple of months. But don't drown it so that it is soggy — you don't want the thick fleshy roots (called rhizomes) to rot.

I’ve noticed that the leaves on my lavender plants in the garden have started to turn yellow. The plants are about four years old and were potted from smaller plants into the flower bed. I’m not sure what the yellow leaves mean or what I should do?

Posted 29/06/2015 by Siofra, Co Monaghan

Hello Siofra, Yellow leaves are a sign that your lavender is stressed. Lavender is a Mediterranean plant, and it grows best on well-drained, neutral or slightly alkaline soil in full sun. If your soil is typical of Monaghan, then it’s probably heavy clay, and the roots are smothering. If you really want to grow lavender, you’ll have to take out the plants and dig in grit or gravel to lighten the soil and help with drainage. Even so, the plants may have to be replaced after three or four years.

Hi there, I’m thinking of investing in a compost bin for the garden – it probably wouldn’t produce that much compost as there is just my wife and me at home now. Is it possible to mix the compost we’d make at home with a bag of compost from the garden centre?

Posted 29/06/2015 by Bill, Co Cork

Hello Bill, I highly recommend a compost bin. Besides the waste from your garden, you can compost all your uncooked vegetable waste, pet hair and the contents of your vacuum cleaner. You can compost torn-up paper as well: corrugated boxes, newspaper and loo roll cores. Paper is useful if your compost is too wet and sludgy. And yes, it is fine to mix your home compost with compost from the garden centre. Just be aware that your own compost will have different nutrient levels from a carefully-formulated commercial compost. You can also use your compost to increase the organic matter in the soil, or as a nutritious mulch for plants.

Hi there, I was wondering if you have any tips for growing sunflowers on balconies. The apartment I live in is north west facing so only gets sunlight early on in the day - is it worth growing sunflowers do you think?

Posted 04/06/2015 by Karen, Dublin

Hello Karen, In theory, sunflowers shouldn’t grow there, because they need lots of light, but it’s worth trying for just one year. There might be enough reflected light that they can use. Sunflowers need loads of water when they are maturing, so be sure to give them plenty to drink. If you are looking for something tall to make a statement, why not try a bamboo in a large pot? Again, you’ll need to water a lot when the new shoots are appearing (around now).

We have a weeping willow tree in our front garden that's about five years old now. We've been able to cut it back the odd bit but now it's got quite overgrown and is blocking some light. Could you offer any advice on cutting back the tree or is it something best left to a professional?

Posted 04/06/2015 by David, Co Carlow

Hello David, If you are talking about a true weeping willow (Salix babylonica), the kind that is often planted on the edge of a lake or river, then this can grow to be a rather large tree. I hate to break the news, but it isn’t really suitable for a front garden, unless you have a huge garden. Willow roots travel extensively, and can interfere with house foundations and drains. If the tree is only five years old, and is already blocking light, consider doing the brave thing and replacing it with a less vigorous tree. Weeping willows can be pruned when the tree is dormant (late winter or early spring), but it is better to just let them have their head. If it’s the small ‘Kilmarnock’ willow, you can prune the branches yourself (cut them back to the bulge at the top of the trunk), but again, do it during the dormant period. With all trees, pruning encourages more growth, so you can easily end up with brush-like sheaves of twigs if you don't prune regularly and carefully. It sounds as if a visit from a professional might answer your questions as well.

Is Shamrock Decorative Bark safe for dogs?

Posted 10/04/2015 by Shane in Dublin

Shamrock Decorative Bark is a completely natural product, made from 100% bark. It is not poisonous for your dog to chew but you should try to make sure he or she doesn't swallow it, since it's not dog food, and may cause your four legged friend some discomfort.

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