Succulents in the Landscape

As water becomes in shorter and shorter supply with this persistent drought here in Southen California, succulent gardens are becoming more popular in place of the more traditional landscapes. There are a few things that I think should be considered, however, when planting succulents in the landscape.

1. Just because they are succulents,you can't just turn the water off on them. The still need a good, periodic, deep soak. Less frequently though in comparison to many other landscape plants. In many cases succulents may be only watered on a monthly basis when planted in the landscape. But they do require some irrigation. There are exceptions particularly during the hottest periods of the summer and/or when planted in full sun. Then succulents will require more frequent irrigation

2. Many succulents perform better in bright filtered light rather than in full sun. This is particularly true the further inland you get. Remember: they are succulents. NOT cactus!

3. Succulents grow. And I think this is the most overlooked aspect when using succulents in the landscape. The typically look amazing when first planted in the landscape. But as they grow, and once many of them bloom, they often get leggy, even straggly, often requiring replanting. I say replanting because once they have bloomed or just gotten leggy there is not much left with many succulents in the landscape. They do however provide good propagation materials for future plantings.

Let it be said that many succulents do hold their forms and look terrific for many years. This does not apply to all species, so choose carefully

The photos below were taken almost a year apart almost to the day at Disney California Adventure in Anaheim, California. You can see just how spectacular the earlier planting looks compared to the same planting one year later.

Something to think about.

Thanks for lookin'
Ron

Taken on 3/21/2014

Taken on 3/31/2015

Growing Stapelia gigantea

Growing Stapelia gigantea

Native to the more arid regions of eastern South Africa, and in the plant family Apocynaceae, Stapelia gigantea makes a great addition to anyone’s succulent collection. The group is referred to as Stapeliads and there are many other plants within this group that are well worth exploring. The plant consists of fleshy, pubescent stems that are segmented into sections about 6” to 8” long, to 1” in diameter, with four ribs running the length of each concave-sided stems. At intervals along the length of the ribs, there are nodes with small, soft spine-like protuberances. The stems typically start out green, sometimes turning purple (particularly in chilly weather) then fade to a silvery-tan as the stems age. 

Stapelia gigantea also called starfish flower, carrion flower or giant Stapelia are really grown for the large 5-pointed star-shaped flower. The flowers can be up to 14” in diameter once opened. They are tan-colored with red streaks across the petals and down into the throat, and have the lovely fragrance of my neighbor’s trashcans on a hot summer’s day. I will say though that you really need to get close to the flowers to fully appreciate the smell, unless of course you are in an enclosed space like a small greenhouse or enclosed patio. As it turns out, flies are the pollinators. All kidding aside, the massive flowers are spectacular! 

Here in Westminster, California (Sunset Zone 22 and USDA Zone 11a) I keep my Stapelia gigantea outdoors in part shade or bright-filtered light under a lattice cover. Although really cold temperatures are rare here, I’ve never really had problems in the few below-freezing nights we do have; probably because mine are protected under that lattice cover. That probably keeps them a bit more protected. The plants do go into a sort of dormancy in the winter months. What often happens at that time is that the stems change to that silvery-tan. The following season new growth often appears from the bottoms of the stems as well as from the tops of the stems. 

Watering and Fertilizing

I usually water when I remember. In other words do not over water these plants. I find they are often best kept on the dry side. Stapelia are relatively slow growing plants. They show growth spurts in the spring and early summer when they come out of their dormancy. More water won’t make them grow any faster so be careful on that count and be patient. 

Propagation

I’ve had a large Stapelia gigantea in a terra cotta pot for over 20 years. Occasionally a stem breaks off, or I will cut off lower-hanging stems and root those. After a couple of days of letting the stems callus, I’ll pot the cuttings up into a coarse, fast draining mix that I typically make for myself. 

Potting Mix

I usually keep these in a really coarse potting soil mix. I use the coarsest, roughest potting soil I can find. They’re often the least expensive, and there are still small bits of wood in the mix. If you can’t find anything like that a cactus and succulent mix works as a good point of departure as well. Then I’ll add plain old brown builder’s sand from the home centers and some Perlite as well. I will usually add orchid mix with small or fine bark too. You can also use small pumice or small cracked gravel—anything that helps hold some moisture but still drains the bulk of the moisture away quickly. I don’t what the plants sitting in a damp and particularly water-logged soil mix. 

Thanks for lookin’!

Ron

Stapelia gigantea flower

Stapelia gigantea plant and unopened bud

Stapelia gigantea rooted cuttings

Zucchini Blossom End Rot

I've been seeing some blossom end rot (BER) in my zucchini. The zucchini plants that I'm growing are volunteers from last year and are doing quite well, but some of the first fruit were showing signs of blossom end rot (see photos below). I always knew it had something to do with a calcium deficiency but wasn't quite sure about all of the particulars. 

As it turns out, calcium, or the lack of, plays a part in blossom end rot of zucchini as well as tomatoes, peppers and watermelon. I was always under the impression that the soil was deficient in calcium, but as it turns out, that's typically not the case. Most soils should have sufficient calcium to support health zucchini, etc. pH can, however, play a big factor in the availability of the calcium to the plants. In acidic soils, soils with a pH down around 5.5 or less, problems with blossom end rot are likely to persist throughout the season. The calcium is 'locked up' to the soil particles (clay particles and organic material particles) in low pH soils making the calcium unavailable for plant uptake. 

Adding a source of calcium to the soil isn't really a solution to correct a current problem. It actually takes several months to become available to plants. And the addition of calcium in already high pH soils can cause problems or deficiencies of other nutrients. Gypsum (calcium sulfate) will provide a source of calcium, but again it needs several months to become available to the plants. Sources of calcium are typically best added in the fall to be available for spring planting. Another possibility is calcium chloride often referred to as "Blossom End Rot Spray." It's water soluble and can be sprayed as a foliar spray over the entire plant. This is supposed to mitigate the problem of blossom end rot as well as being used to set flowers on zucchini, tomatoes, peppers and watermelon. 

Now I like to say that I live on a "sand pile." The soil here in this part of Orange County, California is a silty-sand with a pH very close to neutral or 7.0. And the blossom end rot on my zucchini comes and goes - not persistent. It should also be said that none of the problems causing blossom end rot are caused by disease causing organisms called pathogens. Blossom end rot is caused by various non-living factors like nutrient deficiencies, weather, watering habits and soil drainage. So I had to look elsewhere - referred to as an 'abiotic' disorder. 

As it turns out, there are some other common causes of blossom end rot on zucchini, tomatoes, peppers and watermelon. These problems are more likely to show up as sporadic problems and not continual like those in heavy, low pH soils. Some of the other problems include:

• Harsh changes in temperature (hot or cold snaps) when the fruit are setting
• Low nighttime temperatures
• Excessive irrigation or rainfall
• Heavy soils (clays) causing poor drainage 
• Excessive use of high-nitrogen (N) fertilizers

Now some of these are virtually impossible to control, but we do the best we can to sort it out and determine what the problem is. I'm pretty sure it isn't excess nitrogen fertilizers. Though I do use a commercial fertilizer, it is only 6% nitrogen. The overall temperatures have pretty mild so far this spring so that's probably not it. It has been a bit chilly the last few nights. I suppose that might be a cause. But I'm pretty sure that my problem was too much irrigation. I left the hose on a trickle around the plants and overly saturated the area just about the time the fruit were setting. I'm betting  - and hoping - that was the problem. I'll let you know. 

Some solutions to mitigate blossom end rot where you're pretty sure pH isn't the issue include:

• Addition of compost into heavy, clay soils to encourage better drainage
• Adding compost to sandy soils helps maintain a more balanced soil-moisture level
• Build raised planter beds
• Simply raise your rows higher 
• Install drip irrigation or ooze hose with an irrigation controller 
• When watering by hand - wait until morning to see if plants are still wilting and water then - plants often wilt in the afternoon and recover over night

On a side note:

One way I use to extend my growing season for zucchini as well as other squash and cucumbers, peppers, eggplant, bush beans and more is to build a hoop-house using PVC pipe and 6 mil painter's plastic. It works wonders when low nighttime temperatures are the issue. I'll put up plans in a future post. 

Thanks for lookin'!

Blossom end rot on zucchini

My volunteer plants

Healthy zucchini

Rooting Tomato Cuttings

I started these two tomato plant cuttings from that insane tomato plant from an earlier post. These were side shoots or as some people call them - 'suckers.' I cut them off right above a leaf on the main plant, used a little rootone, stuck them in some potting soil and kept them wet. Off they go!

Thanks for lookin'!

Recycling in the Veggie Garden

I had an old and less-than-safe aluminum ladder laying around and a volunteer tomato plant sprouting. It seemed like a match made in heaven. I have no idea what variety the tomato is since it is a 'volunteer', but it's starting out to be incredibly productive. It's very likely somewhere down the lineage of an F1 hybrid variety that either I or one of my neighbors planted. I'm using sisal twine to tie the plant to the ladder, using the ladder rungs as support. If you scroll through the photos of the plant you can see just how vigorous the plant is. It's finally swallowed the ladder. I have know idea where I'm going to put the rest of the plant. I've got a feeling that it's going to swallow that corner of the yard!

Thanks for lookin'!

Growing sweet potatoes in Orange County, CA.

Sweet potatoes can actually be grown quite easily.

You can get sweet potatoes at the grocery stores, and here in Orange County some interesting varieties in the Asian markets too. Remember, the ones they do sell in the stores as 'yams' are really sweet potatoes too.

Let them sit around until they sprout. Once they do sprout snap those sprouts and root them in small pots. When the sprouts are well-rooted, plant them out in well amended soil. Keep them watered and fertilized and you should have sweet potatoes in the fall.

Thanks for lookin'!