Q. I reside in Karachi and recently imported flower seeds from Germany for Sweet William, Mexican ivy, hollyhock, phacelia, carnation, borage and strawberries. The expiry date on the packets is 2019. I would like to know their sowing time, if they need special handling and how should I store them until it is time for sowing?

A. It’s an exciting range of seeds which should all do well in Karachi with suitable care. The Sweet Williams, hollyhocks, carnations and strawberries can be started off during July and August, preferably in seed trays/pots of good quality compost for flowering/fruiting in late winter and spring. The seed trays/pots will need protection from monsoon rain. Mexican ivy — botanically called Cobaea scandens — is best started off in trays/pots in September/October for flowering in spring but the young plants will need protection from chilly winter winds. You could also start them in a warm, sheltered spot in February/March for summer flowers if preferred. Phacelia can be sown anytime from October till the end of March, whilst borage can be sown right around the year and thrives as long as it gets plenty of water. Storing seeds in an airtight container in the salad drawer of the fridge is ideal.

Q. Will the following bulbs flower in Karachi: Allium, tulips, narcissus, crocus, iris, anemones and daffodils and when should they be planted?

A. Yes to all although their flowering period is shorter in Karachi than in locations with cooler winter/spring temperatures. These should be planted, either directly in the ground or in suitable pots/containers during November if possible but not after December 15, at the latest.

All your gardening questions answered

Q. Can Hawthorn be grown here and what are its uses?

A. Hawthorn or Crataegus Oxyacantha Linn is indigenous in parts of the Northern Areas, KP, Balochistan and Azad Kashmir. Different parts of the plant have various medicinal uses with the ripe berries being especially in demand for treatment of coronary problems.

• Do not use herbal remedies without first seeking professional advice.

Q. I planted ginger last August and need to know when would it be ready for use. I live in Karachi.

A. Ginger is best started off in very early spring. It needs a minimum of eight months to produce a tuber of a decent size in well-prepared soil. This eight-month growing period needs to be primarily in hot, sunny weather and not over the winter months when temperatures are too low for tuber development.

Q. I am struggling to grow healthy, beautiful crotons in Islamabad. They are all in large pots, happy during summer but cannot survive winter. I have tried moving them indoors when night temperatures are low and then putting them back outside on sunny days but this hasn’t saved them. It breaks my heart to lose such lovely plants. Is there any way they can be maintained all year round?

A. Crotons are tropical/subtropical plants and need both warmth and humidity all year round. The only way to achieve this in Islamabad is to place them in a warm greenhouse throughout the cooler months, heating the greenhouse if necessary and maintaining a certain degree of humidity therein.

Q. How can hard-shelled seeds such as chikoo and lychee be germinated? I have tried many times but failed.

A. Hard-shelled seeds are generally subjected to ‘stratification’ to help them germinate. Depending on the seed species, stratification is achieved by either subjecting the seed to a period of freezing conditions followed by heat followed again by freezing. Doing the latter in the kitchen freezer is fine although as the stratification period varies quite widely from species to species, I cannot specify the length of time. Alternatively, use rough sandpaper to vigorously rub an area on one side of the seed until this area thins enough to allow a germinating shoot to break through and grow.

Q. I have been observing very tiny white insects underneath the leaves of annual plants which are making the leaves curled up and twisted. What is the remedy?

A. This is white fly and simple to eradicate at the first sign of an infestation. In the evening, spray warm, soapy water on both the under surface as well as the upper side of the leaves.

Q. White lines have developed on leaves of marigolds, petunia, chrysanthemum, dahlia and some other types of plants in my garden. How can this disease be controlled or removed from fully-developed plant leaves?

A. The problem is leaf miners: these are the larvae of certain types of moth, sawflies, beetles or flies. They munch away on tissue inside the leaves. The white markings are the tunnels they create. If just a few leaves are infected, cut off the leaves and dispose of them away from your garden. If many leaves are infected then it is best to remove those plants completely. The best organic control is to squash the larvae inside the leaves at the first sign of attack.

Please continue sending your gardening queries to zahrahnasir@hotmail.com. Remember to include your location. The writer does not respond directly by email. Emails with attachments will not be opened.

Published in Dawn, EOS, April 9th, 2017