Damaged tomatoes, stunted irises? Gardener tells why

Q My tomatoes are starting to ripen, but the ends are turning black and getting soggy.

Is there some insect or disease that is causing this? What can I do about it? — R.G., Castro Valley A No insects or diseases. It’s called blossom-end rot, and although it can be common in tomatoes, it also happens in peppers, squashes, cucumbers and melons.

It’s caused by a lack of calcium, but that doesn’t mean that your soil is lacking in calcium. It probably isn’t. It’s usually more of an irrigation problem. The water is what carries the calcium up into the plant, but if the watering has been inconsistent, the end of the tomato can rot.

For example, if you started your garden by giving seedlings lots of water, then forgot to water as often as you should, end rot can occur.

You don’t want to eat the nasty looking part of the tomato, but you can cut off the bad part and eat the rest. To prevent the condition with future tomatoes, make sure you have a consistent watering schedule. Q I am hoping you can help me identify what is wrong with one of my irises. The flowers are stunted and do not look like they are supposed to. Any ideas? Insects or a virus? I have asked around and no one seems to know. — Larry Switzer, BAY Area

A The root of your problem is, most likely, in the iris bulb. If the bulb was mushy or rotten, or small or undersized, it can produce stunted blooms, and in some cases, no blooms at all.

When you plant bulbs, they can look normal but then rot in the soil if it’s too wet. Sometimes older bulbs get accidentally mixed in with new ones that you purchase. Or if you dug up your irises, divided and replanted them, you might have planted a bulb that was just spent. It happens.

As you have other irises that bloomed normally, it doesn’t seem that you have a soil issue or an insect one. Mark the plant, and the next time you divide your bulbs, toss that one out.

Do you have a gardening question about outdoor plants or house plants? Send your questions to Joan Morris at jmorris@bayareanewsgroup.com.