Gardening Q&A

My gardenia buds turn brown and fall off. Why?

Gardenias like to be kept moist, and bud drop is often associated with too little water. Typically, the buds turn brown or black and fall off before opening. Make sure the plant stays moist, but not waterlogged. Gardenias also drop buds when they are moved. If you recently planted or transplanted the bush and it is dropping buds, let it get settled and the problem should remedy itself.

The leaves on the tip of my "Howard McMinn" manzanita are curled and swollen and turning red.

The leaf curling is caused by the manzanita leaf gall aphid. It is usually harmless to the plant, although a little disfiguring to the new growth. Your manzanitas are likely being too well cared for and getting too much water. Cut back on the water and don't fertilize the plants either. Next season, apply a horticultural oil just before the new leaves appear in the spring if the problem persists.

I have a question about climate zones. One book says I live in Zone 9 while another says I live in Zone 27. Which is correct?

Both. Zone 9 is your USDA zone and Zone 27 is the "Sunset Western Garden Book" zone. The Sunset zone system is quite a bit more detailed and takes into account more than just the last frost date or lowest average temperature. In fact, Zone 9 could and does cover some areas that only get down to low temperatures for a few hours; other areas in the same zone might have those same low temps for days or weeks on end. It's a guide.

I never got around to pruning my forsythia, and it's a tangled mess. Can I still prune it?

No, don't prune it now or you'll be cutting off all of this year's flowers. The time to prune spring-blooming shrubs such as forsythia is right after they bloom. Wait until this year's flowers are gone, and then give the bush a good pruning. First cut away any dead or crossing branches. Then step back and take a look. This might be all you need to do. Next, prune to shape the shrub or to keep it in bounds. When you're done, the plant should look as though it grew that way naturally.
 

How do I start tomatoes now so I have good-sized plants for spring?

It's a little more complicated that just dropping seeds into a pot. You need to fool the seeds into thinking it's spring, that the ground is warming and it's time to sprout. The best bet is using a warming pad under the pots, and then having lights hung just above the pots to use when the seeds sprout. Most garden centers carry all the supplies you'll need, and there's also plenty of detailed help online.

My scented geraniums are showing some signs of damage from the cold. Can I save them?

The hardiest ones are the rose-scented geraniums. The most frost-susceptible is the peppermint geranium. However, even if the foliage is damaged and needs to be cut completely back, the root system is usually fine, and the plants come back as soon as it is safe. When the nights or days are going to be chillier than the plants can tolerate, cover them with a light blanket or newspaper. There are also covers you can buy at the local garden center to protect plants from frost. Even dumping leaves over the plant will offer some protection. If it's a geranium that is hard to replace, take some cuttings, put them in soil and bring the pots inside.