Martin Fish, our friend from Pots & Trowels, answers your gardening questions and solves your niggling plant problems in our gardening tips Q&A blog this week. Keep reading for his expert advice and watch the videos below to get even more information!

Which variety of rose is best to plant for climbing?

We all want to grow the perfect climbing rose plant around our garden trellis or over our front door. The flowers look stunning and bring wonderful colour in the summer. The rose variety Zéphirine Drouhin works perfectly for climbing. It’s a lovely compact rose that doesn’t get too many thorns, plus it’s got a glorious scent too. Our friends at Mr Fothergill’s sell a wide range of bare root rose plants and rose care products to help you create your dream garden.

What causes the leaves on roses to turn yellow?

That unsightly yellow colour on our roses is such a pain, and it’s so disappointing to see. Yellowing leaves on roses can be caused by several things:

• It could be a lack of water, causing stress to the plant. Often a rose will lose its bottom leaves for protection if it’s in drought and hasn’t had enough water. Be sure to give your yellow-leaved rose a good drink, adding some liquid feed if necessary. Hopefully, the new growth will then be better.
• Yellow leaves could also be a sign of the start of black spot. If that is the case, you can spray the rose with a fungicide. Do note that this will only protect the new growth.
• Be sure to prune the discoloured leaves and keep on top of aphid control.

What grows well under tree shade in the garden?

Ground cover plants grow well under the tree shade canopy in your garden – as long as there is moisture to support them. This semi-shaded spot is perfect for planting ivy or geramium macrorhizzum as they will provide colour. You could even plant some hardy ferns as they will tolerate drier, fairly shady spots. Snowdrops, daffodils and bluebells will also look great in the spring. Remember to water the plants well for the first season to allow them to establish.

Can potted dahlias have too much rain?

Drainage is important for all potted plants. Often it’s not a case of too much rain, but not enough drainage. When you pot any plant, make sure you add draining holes as the roots can get waterlogged and rot. By allowing the water to drain, you allow the roots to grow. Remember to only water your dahlias when the compost starts to dry out. If they are still needing some help to bloom, it could be worth adding a little feed to perk them up.

How to stop cats from littering in the garden?

Cats love soil when it has been worked and is soft. That’s because it’s easy for them to dig up a hole and then use it for littering. One solution for this pesky problem is to use sonic cat scarers (or cat repellents). They emit a loud, high-pitched noise and have a flashing light that cats don’t like. It doesn’t harm them, but it keeps them away. You can then move the scarer around the garden so the cats don’t know which direction they can enter from. These scarers can be solar-powered and will help solve your cat problems without causing harm.

How do you know when garlic is ready to harvest?

It’s crucial to harvest your garlic at the right time. Be sure to wait until the tops of your garlic have really died down before you lift them. Whilst the leaves are green, the bulbs are still growing. It’s only when the leaves have all gone yellow and fully dropped that you should harvest your garlic from the garden. To harvest your garlic, gently lift it from the ground with a fork or a trowel, being careful not to damage the bulb. Depending on where you live, this is normally from July through to August. The Darlac 5-in-1 Tool is a fantastic product that can help with a variety of harvesting tasks.

If you’ve enjoyed these quick-fire questions then Martin has even more advice on these topics – watch the full video to find out more!

When is the best time to prune peonies?

There are two different types of peony; the herbaceous flower which is in flower in the summer, and the tree peony. The herbaceous type usually dies down in the autumn and doesn’t need to be pruned. However, if you have a tree peony, which forms into a large shrub, then it will need to be pruned immediately after flowering. These plants usually flower in the spring, therefore pruning will be needed by the summer. However, these shrubs don’t need heavy pruning, just thinning out and shape maintenance.

How to manage a lilac tree?

If you prune your lilac tree back it will encourage it to bush out. This might mean a season with fewer flowers whilst the growth happens. Lilac flowers form at the end of summer, so pruning needs to happen at the beginning of the summer (at the latest). Encouraging side growth in this way will lead to more flower growth. Be careful not to prune too much, you only need gentle pruning for this plant. The ideal time to prune for the future will be immediately after the flowers have faded. If you are looking for an ‘all-round’ pruner to help you with various gardening jobs, the Darlac Expert Bypass Pruner is a great choice. With a large cut capacity, yet slimline handles, it’s a great tool that you’ll use time and time again.

Why does my iceberg lettuce turn reddish brown at the edge?

Growing your own fruit and veg can be really rewarding, but it does often come with a steep learning curve. Growing lettuce is a great place to start.

Lettuce leaves turning reddish brown usually happens because of nutritional disorders, such as lack of water or food, meaning the plants aren’t getting the nutrients they need. Ensure you are giving them lots of water and don’t let them get dry. As we’ve had a hot summer, it could be heat damage too. Be sure to add some extra feed and see how they develop. The good thing to note is they can still be eaten!

How often should you feed a tomato plant?

A tomato plant needs to be fed every week to get the fruit to swell and ripen.

What’s the best way to get rid of aphids on roses?

Unfortunately, aphids come back to our roses time and time again, and getting rid of them isn’t a one-time thing. It’s a case of little and often. Every few weeks, make a point of checking your plants. You can rub aphids off with your fingers, or use a soap and water spray to get rid of them. Good luck!

Martin took time out from his work at RHS Harlow Carr to answer these questions, and offers even more advice for your gardening queries in the full video below:

You can also catch up with Martin and his useful gardening advice in the Darlac monthly newsletter, sign up here to get regular updates from Darlac and read Martin’s advice.

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