Need Help re Raised bed

[Wildcat82]

I've read pomegranates grow in just about any soil so I planted 2 pomegranates (Salavatski and Parfianka) directly in my Texas Blackland Clay soil here in San Antonio. Three years later there was zero growth on the plants so I pulled them out. It took no effort at all since I found out the roots did not penetrate my hard soil at all - they had just crawled horizontally an inch or so deep.

Next I tried planting new seedlings in a 4' by 4' by 12 inch deep raised bed. After 5 years my Parfianka is 5 foot tall and has never even bloomed and my 5 foot tall Salavatski has set only couple golf ball sized poms. Both plants seemed healthy. This spring I see they both died back to the ground despite a very mild winter here. I've been stumped trying to figure out why my poms simply don't grow well here.

I recently found one article that claimed pomegranates roots grow shallow and wide. Perhaps my 4' by 4' bed is too small to allow them to grow as they should. Do I need to put in much bigger raised bed, say an 8' by 8' by 12" deep raised bed? Do you think that would help?

[alanmercieca]

I think that it's a combination of the hot dry summers, and the fact that raised beds dry out faster than the ground does. Texas summers are hard on pomegranates as it is, adding the a raised bed to the environment makes it worst. You could try watering the bushes 2 times a day, during the hotter months, and it would help if you'd wet the whole plants each time that you'd water in the hotter months, leaves and all. Once in the morning, and once in the evening as the temperature starts to cool down. It would also help if you put shade cloth over the ground, to help slow down the drying of the dirt. If that is not good enough you could try putting a fine net around each of the two plants during the hottest months, that would help shade the plant a little while helping to prevent the fruit skin from burning.

The kind of pomegranate bushes that most people grow today, were created by rooting cuttings, they do have shallow roots. Yet the old fashioned way to reproduce pomegranate bushes was to germinate pomegranate seeds, and either use the seedlings as root stock. Or just use the seedling as their pomegranate bush. Seedlings have much deeper and stronger roots, which not only gets water, and moisture from deep down, also nutrients from deep down as well. Yet a lot of places that pomegranates are grown today, are too wet at least part of the year for deep roots to make sense.

Mild winters/springs can be much hardier on pomegranate bushes, than actual cold are on them. I looked at your forecast the last winder/spring, and I'd be surprised if they did not get any damage, many times it had went from freezing to warm or hot weather just hours later, that is dangerous for a pomegranate bush. There was only one month that actually had any hard freezing in your area.

[pogrmman]

Up here in Austin on the edge of the plateau, I haven’t noticed issues from soil — poms seem to grow fine in my native, "extremely stony clay" (as described by the soil survey for Travis Co.) or in that nasty red clay contractors bring in as fill.

Currently, my inground plants are both in the latter fill soil, planted at the top of retaining walls. Not very wide, but plenty of depth.

You're definitely right that the Blackland Prairie clays can be extremely dense and hard, especially when they’re dry. I think some soil amendment with organic matter is definitely in order — although poms aren’t super picky about that, many Central Texas soils are deficient in organic matter. It’ll help to improve the tilth of the soil and also improve water infiltration.

I also think the raised beds may be drying out — and with the way the clays on that side of the escarpment work, plants aren’t always able to get down passed the raised bed soil.

Regarding dieback this winter, although it’s been mild overall we got very very cold in December. Because it had been relatively warm up until then, the trees probably weren’t fully dormant. One of my pomegranates still had some foliage when that freeze hit and it has a couple feet of dieback. Another one was completely dormant and had no dieback at all. In San Antonio, the lack of dormancy was probably worse than it was up here in Austin and y’all weren’t really any warmer than we were. This is generally the biggest issue with cold in our area — not the actual magnitude, but the warmth preceding it.

[Wildcat82]

Up here in Austin on the edge of the plateau, I haven’t noticed issues from soil — poms seem to grow fine in my native, "extremely stony clay" (as described by the soil survey for Travis Co.) or in that nasty red clay contractors bring in as fill.

Currently, my inground plants are both in the latter fill soil, planted at the top of retaining walls. Not very wide, but plenty of depth.

You're definitely right that the Blackland Prairie clays can be extremely dense and hard, especially when they’re dry. I think some soil amendment with organic matter is definitely in order — although poms aren’t super picky about that, many Central Texas soils are deficient in organic matter. It’ll help to improve the tilth of the soil and also improve water infiltration.

I also think the raised beds may be drying out — and with the way the clays on that side of the escarpment work, plants aren’t always able to get down passed the raised bed soil.

Regarding dieback this winter, although it’s been mild overall we got very very cold in December. Because it had been relatively warm up until then, the trees probably weren’t fully dormant. One of my pomegranates still had some foliage when that freeze hit and it has a couple feet of dieback. Another one was completely dormant and had no dieback at all. In San Antonio, the lack of dormancy was probably worse than it was up here in Austin and y’all weren’t really any warmer than we were. This is generally the biggest issue with cold in our area — not the actual magnitude, but the warmth preceding it.

Five years ago I filled by raised beds with Miracle Grow garden soil, a couple bags of Black Kow composted cow manure per bed and about 25% native clay soil. Two years ago I planted 2 more pomegranates in a similar mixture. I think there's enough organic matter there.

I don't think my beds are drying out. I have rabbiteye blueberries (with their extremely shallow roots) planted adjacent to the pomegranates in similar raised beds and they never seem to suffer. I've learned to pile up a full foot of pine bark mulch (about a foot away from the trunks) around my peaches, blueberries, and pomegranates to make sure the roots don't cook and stay somewhat moist. I also dug a foot down under my beds to allow for more root room. This basically forms a small perched aquifer under the pomegranate. I dug one of my Parfiankas out yesterday and the roots looked fine so no root rot.

You're probably right about our climate causing problems with dieback.