Is it too late to plant zucchini seed?
No, but get cracking - plants are prone to powdery mildew later in the season. Choose a sunny spot and plant seeds directly into mounded soil enriched with well-rotted manure or compost. Blackjack is a reliable variety, with four or five plants usually enough. Keep watered in dry weather, watering below the leaves rather than using a sprinkler as wet leaves encourage downy mildew. Pattypan squash make an interesting variation; they taste similar and are grown in the same way.
How do I get rid of whitefly in my garden?
With difficulty. Although adult females live only for a month, in that short time each one will lay up to 500 eggs. Whitefly tend to proliferate when their natural predators (such as ladybirds and spiders) are absent, which could be down to anything from dusty weather conditions to pesticide use. Control measures include sticky yellow traps, removing weed hosts, getting rid of ants, high-pressure hosing and (if you must) repeated applications of an insecticide such as Target or Orthene.
If you have a gardening question, email Glenys at firstname.lastname@example.org