Climber is the Guadeloupe cucumber
A plant is creeping along the fence belonging to my mother. All its fruit fell off during last week's storm. I found one on the ground and it was dark green. Is it a Mexican sour cucumber?
Lim Su-Ching
The plant is commonly known as Guadeloupe cucumber. Its botanical name is Melothria pendula.
It grows as a climber and occurs mostly as a weed in Singapore. It is rather fast growing and can smother nearby plants by enveloping them.
Its immature, green fruit is reported to be edible. It turns black when ripe and at that stage, it should not be consumed due to its strong laxative effects.
Gunpowder plant's blooms shoot pollen into the air

What is the cluster of small plants in the pot? It came with a pot of pomelo leaves I bought.
Geraldine Choy
The plant with small leaves is found as a weed growing in flower pots and garden beds.
Botanically known as Pilea microphylla, its common names include artillery plant and gunpowder plant.
The story behind these two common names is due to a curious habit of this plant, which has small flowers that reportedly shoot pollen explosively into the air.
Plant can be propagated via stem cuttings

If I cut the branch off this plant and repot it, will it grow?
Paulyn Lim
The plant is likely the Leuenbergeria bleo, a leafy cactus species commonly known by its local Chinese name, "Seven Star Needle".
This plant can be propagated via stem cuttings. You can prune lanky stems off your existing plant to ensure branching of the main plant.
Cut the stems into shorter sections measuring about 15cm long, and put each stem into a container with well-drained and moisture-retentive potting mix to root.
Cut large leaves in half to reduce water loss from the stem cutting. Place the new stem cuttings at a bright but cool corner of the window.
Papaya has been infested with mealybugs

My papaya tree has recently been producing fruit that is black. There appears to be scales and fungi growing on it. However, when I wash the fruit, the skin underneath looks fine and the flesh is firm and orangey. Is the papaya edible?
Karen Ang
The papaya is generally edible after you remove the skin.
The white cottony masses on the fruit are mealybugs, which are very common but serious pests for this plant. They excrete honeydew, a sugar-rich liquid that coats the fruit and leads to the growth of sooty mould.
A very heavy infestation of mealybugs on your papaya plant can weaken it.
To manage this pest in the home garden, check your plants regularly. You can use a strong jet of water to wash off pests, then use neem or summer oil to suffocate them. Regular pesticide applications are needed to provide control.
Also, try to grow shorter varieties of the plant, which makes it easier to check and control the population of the pest.
• Answers by Dr Wilson Wong, an NParks-certified practising horticulturist, parks manager and ISA-certified arborist. He is the founder of Green Culture Singapore and an adjunct assistant professor (Food Science & Technology) at the National University of Singapore.
• Have a gardening query? E-mail it with clear, high-resolution pictures of at least 1MB, if any, and your full name to stlife@sph.com.sg. We reserve the right to edit and reject questions.