Monthly Q&A: Get Expert Gardening Advice
Finding Answers to Your Gardening Questions
Every month, our expert horticulturalists answer a selection of your gardening questions. Submit your questions for a chance to have them featured in our monthly Q&A video.
August 2023 Q&A
Controlling Red Spider Mite in Greenhouses
Red spider mites are tiny pests that can infest greenhouses, causing damage to plants. To control them, try using insecticidal soap or neem oil. You can also increase humidity in the greenhouse by misting plants regularly or placing a humidifier nearby.
Growing Raised Beds on Gravel
Yes, you can place raised beds for vegetables on top of gravel. However, you need to ensure that the gravel is well-drained to prevent waterlogging. You should also add a layer of landscape fabric between the gravel and the raised bed to prevent weeds from growing.
Dahlia Pests and Diseases
If the leaves and flowers of your dahlias have been eaten, it could be due to pests such as slugs, snails, or caterpillars. To control these pests, you can use slug and snail bait or insecticidal soap. You can also try companion planting with marigolds or nasturtiums, which deter pests.
Dealing with Cleavers on Compost Heaps
Cleavers are a common weed that can infest compost heaps. To remove them, you can pull them out by hand or use a hoe to cut them down. You can also cover the compost heap with a tarp or cardboard to block out light and prevent cleavers from growing.
Preventing Lavender Plants from Flopping Over
Lavender plants can flop over due to several reasons, including overwatering, too much fertilizer, or lack of sunlight. To prevent this, make sure to water your lavender plants deeply but infrequently. Avoid over-fertilizing, and provide your plants with plenty of sunlight.
Additional Gardening Questions and Answers
July 2023
- How to control weeds in your garden
- Encouraging flowers on lower stems of ‘Gertrude Jekyll’ climbing roses
- Troubleshooting beetroot and radish development issues
- Propagating plants from basal and root cuttings
- Choosing plants for hot, dry summers
June 2023
- Preventing pear midge from damaging pears
- Moving an acer tree planted six weeks ago
- Identifying and treating brown leaves on agapanthus plants
- Using two-year old comfrey feed
- Disposing of dug-up Spanish bluebells
May 2023
- Growing potatoes in grow bags under apple trees
- Treating black spot and rust on roses
- Fertilizing new tomato plants
- Understanding the difference between vermiculite and perlite
- Reusing old compost from containers
April 2023
- Alternatives to artificial lawns
- Pruning time for lilacs
- Troubleshooting brown foliage on moth orchids
- Encouraging flowering in tulips
- Extending the flowering period of sweet peas
March 2023
- Creating a wildflower meadow from a small patch of lawn
- Planting climbing roses in winter
- Planting and caring for chitted potatoes
- Maintaining a lawn: scarifying, mowing, and weed and feed
- Moving seedlings from propagators to windowsills
February 2023
- Reviving winter-damaged evergreen agapanthus
- Pruning fuchsias in winter or spring
- Moving Salvia x jamensis ‘Hot Lips’
- Eliminating mealybug on orchids and streptocarpus
- Growing asparagus in raised beds
January 2023
- Identifying and treating leaf loss in pittosporum
- Understanding stunted leek growth
- Managing pine needles at the base of trees
- Planting spring bulbs in late winter
- Pruning sambucus trees
December 2022
- Using water from a smelly water butt
- Caring for banana plants in winter
- Encouraging reblooming in amaryllis
- Controlling woolly aphid infestations on beech hedges
- Troubleshooting beetroot plug failure
November 2022
- Utilizing greenhouses over winter
- Winter mulching perennials without burying crowns
- Improving flowering in old climbing roses
- Removing variegated alder trees with coral spots
- Eliminating worm casts from lawns
October 2022
- Improving water retention in peat-free compost
- Pruning summer- or autumn-fruiting raspberries
- Removing large, unripened figs
- Controlling fuchsia gall mite
- Potting or planting newly purchased perennials
September 2022
- Reusing old compost effectively
- Using pot feet or saucers for containers
- Reviving a damaged lawn
- Troubleshooting wisteria dieback
- Treating brown rot in plum trees
August 2022
- Rehydrating dehydrated potted hydrangeas
- Understanding ‘loam’ and its benefits for compost
- Controlling black spot on roses without spraying
- Troubleshooting runner bean failure
- Identifying the cause of brassica plants with no centre
July 2022
- Watering frequency for dahlias and sweet peas
- Managing powdery mildew on plants
- Taking cuttings from leggy pinks
- Understanding why vegetable plants produce all leaves and no fruit
- Identifying and managing non-fruiting stems on summer-fruiting raspberries
