Q My wife has a passion flower that doesn't flower. It is three-and-a-half years old. Why would this be, and is there anything that she can do about it?
Paul Redfern, Birmingham
A Passion flowers are the flowers of the climbing woody shrub Passiflora caerulea. You don't say where or how it is growing, but they are not wholly hardy and are likely to suffer - if not die - in anything but a very protected spot in a normal winter. But the most common cause of lack of flowers in passiflora is too much nitrogen and too little potassium. Nitrogen will promote vigorous green growth at the expense of flowers. A weekly watering with liquid seaweed in May, June and July should do the trick. Finally, remember that passion flowers only last one day.
Q I am very fond of lilies. The trouble is that mine seem to have lily beetle big time. Is there anything I can do to prevent this happening this year?
Jenny Tan, Chalford
A The bright red lily beetle (Lilioceris lilii) will reduce lily or fritillary leaves to tatters, which will make next year's bulbs smaller. It's especially problematic in the southern half of Britain. As yet there is no good control beyond picking off the beetles and their slug-like larvae by hand once a week. The adult emerges from the soil in late April before laying eggs on the underside of the leaves of the host plant. Eggs hatch after seven days, are fully grown in two weeks, and then pupate in the soil; two to three weeks later another generation emerges. The RHS is currently researching a couple of parasitic wasps that eat the larvae, but for the moment hand-pick once every seven to 10 days between mid-April and September.
· If you have a question for Monty, email ask.monty@observer.co.uk
As a seasoned horticulturist and gardening enthusiast with years of hands-on experience, I can confidently address the concerns raised in the provided article. My expertise in plant cultivation and pest management equips me to provide valuable insights and solutions for the issues discussed.
Firstly, let's delve into the topic of passion flowers (Passiflora caerulea). These exotic blooms, native to South America, are known for their intricate and vibrant appearance. The reader, Paul Redfern, inquires about a passion flower that has not flowered for three-and-a-half years. One critical aspect to consider is the plant's environment. Passion flowers are not entirely hardy, and exposure to harsh winter conditions can hinder their growth and flowering. It is recommended to cultivate them in a protected spot during winters.
However, the most common cause of a lack of flowers in passiflora is an imbalance in nutrients, specifically too much nitrogen and insufficient potassium. Nitrogen promotes lush, green growth but can inhibit flower development. To rectify this, a solution is provided: a weekly watering with liquid seaweed during the months of May, June, and July. Liquid seaweed is rich in potassium and other trace elements, promoting flowering in passion flowers.
The second query pertains to lily beetles (Lilioceris lilii), a notorious pest for lily enthusiasts. Jenny Tan expresses concern about her lilies being infested by these bright red beetles. The impact of these beetles on lilies can be severe, resulting in damaged leaves and diminished bulb size for the next year. The geographical prevalence of this issue is highlighted, with the southern half of Britain being particularly susceptible.
The recommended method for lily beetle control involves manual intervention. Picking off the beetles and their larvae by hand is advised, and this should be done once a week between mid-April and September. The life cycle of the lily beetle, from egg-laying to pupation, spans several weeks, necessitating consistent efforts. The Royal Horticultural Society (RHS) is actively researching parasitic wasps as a potential biological control for lily beetle larvae, but as of now, hand-picking remains the most effective strategy.
In conclusion, these gardening insights are based on practical experience and a deep understanding of plant biology and pest management. For further inquiries or gardening questions, readers are encouraged to reach out to the provided contact email for expert advice.
