Slime mold fungus in lawn causes no harm

Q: We have this ugly grayish gelatin mass growing in our lawn. They are slimy like slugs. Can you help us out?

A: The color throws me off a little bit because I think this is one of the slime mold fungi. Usually, the color is yellow or yellow-orange or brown and even black, but I’ve not seen it grayish-white before. This is the right time of year for it to pop up in lawns so I’m going with it.

Nothing to be overly concerned about. It’s not toxic, but it’s not edible or palatable either. Some people have reported their dogs eating it and then throwing up. Maybe that’s why it’s given the common name “dog vomit.” Dog vomit is what it looks like in many cases.

Slime mold fungi are particularly disgusting because they are gelatinous and, over time, change color if they’re left undisturbed. When they change color, they are more noticeable and attract attention. The color change is because the fungus matures and starts reproducing unless you break it up with a rake or the nozzle of a hose and wash it into the soil.

The biggest problem I see with slime molds is suffocation of the grass because they can lay on top of it and smother it. These slime molds also grow on wood chip mulch. It usually happens after a good rain or a heavy irrigation with lots of humidity. Dog vomit fungus will happen in full sun. It doesn’t need shade like algae does.

Break it up when you see it, wash it into the soil with a strong stream of water and that will kill it if you get it early enough. If you catch it when it’s a dark color, it may be ready to spread and might pop up again somewhere nearby.

Q: The tops on my garlic have all dried out and turned brown. Is it time to dig up the bulbs?

A: Garlic and onions grow well in our Southern Nevada climate. Most of the information available tells you to harvest garlic when half of the tops have turned brown. I think this is too late.

I tried following this advice years ago and found this was a little bit too long to leave garlic growing in the ground. The tops will progressively turn more and more brown from the top to the bottom. When garlic is left too long, the paper membrane around the cloves begins to disintegrate exposing the cloves. It doesn’t hurt the garlic but it’s not pretty to look at.

I have found the best time to harvest garlic is when one-third of the tops have turned brown, not half. It doesn’t sound like much of a difference, but it can be the difference between having pretty garlic and not.

Unlike onions, don’t wait for the tops to fall over before harvesting. That would be a mistake. By the way, I have probably tried about 25 varieties of garlic and have never been skunked by either hard neck or soft neck varieties. I clean and then hang them in the shade in open air to dry.

Q: I am growing Early Girl, Green Zebra, Chocolate Sparkles, yellow pear tomatoes, Sweet 100 cherry tomatoes, and they are all producing lots of vines, but the flowers don’t seem to set much fruit.

A: I like it that you are spreading the risk of failure around. The spring weather in Southern Nevada can be very erratic, both temperature and wind. A garden will perform much better if it’s protected from the wind with a small windbreak. Farmers know their best production is on the leeward side of a windbreak. Yours will be too.

When selecting tomato varieties, include some tried and true types that are more likely to give you success such as Early Girl, Celebrity, Champion, Patio, paste tomatoes like San Marzano, even Better Boy and Best Boy. Select determinate forms of these tomatoes when possible rather than indeterminate forms.

Determinate forms are quicker to produce fruit and don’t focus their energy on growing a bunch of vines early in the season. Indeterminate types will.

Grow a mixture of different varieties of tomatoes and “don’t put all your tomatoes in one basket.” If you want to grow heirlooms such as Green Zebra, don’t grow all Green Zebra but put a few in and see how they perform for you. Personally, I tried them, and they didn’t produce very well, but I only tried them for two seasons.

If you have success one year with a variety, don’t go telling everyone to plant that variety. It’s tempting but that can be a big mistake because our weather is so variable in the spring. One year it can be the perfect spring and the next spring you might get nothing. For me, I withhold judgment until about the fifth year of solid production.

Q: I planted a bottle tree in January, and I am now deep-watering this tree about once a week. It’s getting new growth buds, but then they turn brown and stop growing. What am I doing wrong?

A: I don’t have a lot of information to go on but soil moisture, too much or too little, can cause what you’re talking about. Transplant shock can also play a role. Make sure the tree was planted at the same depth as it was in the container.

Overzealous planting can result in huge holes where the soil settles, along with the plant, thus burying the trunk 3 to 8 inches too deep. This leads to collar rot that chokes the waterways from the roots.

Check the easy stuff first. Make sure the tree hasn’t settled in soft soil and the trunk buried too deep. Pull the soil away from the trunk and make sure the surface roots are no more than about one-half inch deeper than the surrounding soil.

I don’t like big holes but sometimes they are necessary. If the soil drains water in six or eight hours or less there is no need to dig a big deep hole. It is more important to dig the hole wide than deep if the soil drains water adequately.

Settle the soil around the root ball and remove air pockets the first two or three days after planting. This means the hole will be very muddy for a couple of days. Then give the soil a chance to dry out before watering again.

All soils are different but irrigate when the soil is on the dry side at about 2 or 3 inches deep. If I don’t know the soil, I use a soil moisture sensor to help judge when the soil is starting to dry out. You can buy inexpensive sensors made for watering house plants or expensive moisture sensors used for measuring the water content of compost.

The magic number when to irrigate is “5” on the moisture sensor. It should read or be adjusted to 10 right after an irrigation.

Transplant shock is the time needed for the plant to begin growing again after it’s been planted. All plants get transplant shock after planting. Sometimes transplant shock is very short-lived and the plant perks up in a few days after planting. Other times it can take weeks or months.

The degree of transplant shock, or how long it takes to recover, depends on the state of the plant at planting time, how big it is, how it was planted and managed after it was planted. Plants grown locally exhibit less transplant shock than those imported from mild climates. Smaller plants have less transplant shock than larger plants.

The skill of the planting team plays a huge role in transplant shock. It’s important to not let plant roots dry out and gently ease the tree into the planting hole.

Most times the soil needs amendments at the time of planting. If the soil is terrible, more amendments are needed, or the soil should be replaced. Plants should never be planted and left for any length of time in a dry hole but immediately watered at the time of planting.

If I were to bet given the information I have, I would guess the soil is drying out too much between irrigations. But remember, plants can react to overly wet soils the same way they react to overly dry soils. Check the soil moisture before irrigating.

Bob Morris is a horticulture expert and professor emeritus of the University of Nevada, Las Vegas. Visit his blog at xtremehorticulture.blogspot.com. Send questions to Extremehort@aol.com.