Of Raised Beds and pulling down to correct level

Mary Sue Ittner msittner@mcn.org
Sun, 14 Aug 2005 13:47:46 PDT
Dear All,

In July there was an interesting discussion about whether bulbs pulled 
themselves down to the level they preferred. I'm not sure there was 
consensus about this. Many of us have found bulbs on the bottom of our pots 
when we repotted, but some of them could have been offsets or droppers. A 
number of years ago before I became addicted or passionate, depending on 
your definition, about bulbs I purchased native California bulbs from the 
Robinetts. Their advice was deep pots and planting 3 or 4 inches deep for 
Brodiaeas, Triteleias, Dichelostemmas, and deeper still for Calochortus. 
They recommended good garden soil for the first three with sand added for 
drainage and good drainage for the latter. I started out with smaller pots, 
but when I finally followed their instructions with a deeper pot had more 
success translated to bigger corms or bulbs and more flowers. The same was 
true when I used a less lean mix.

When we moved to the Northern California coast, my husband built me some 
raised beds so I could grow my bulbs in them and leave them dry in summer. 
The idea was to save time and energy as I would not need to repot every 
year. A number of years ago Alberto Castillo helped me with a winning 
combination for converting these beds where the bulbs were planted directly 
in the soil to beds where they are planted in pots with much more control 
of the environment, soil, and ease of making changes in what is growing 
there. Each year since I've been converting a bed which has been a horrible 
job requiring digging out all the soil and starting over. This year I have 
tackled the first one Bob created for me. We aren't sure how many years we 
have had it, perhaps 14. This bed was supposed to be for natives. I used 
the "good soil" we had purchased to improve our nutrient depleted sandstone 
soil. This soil removed when houses were being built closer to the ocean 
was a rich dark color, but I soon learned was not worth purchasing. It has 
the consistency of silt and is nutrient deprived as well. Water just rolls 
right off of it and when you get it on your clothes, they are never clean 
again. It's main advantage seems to be that it comes with weed seeds so my 
garden soon had our local California poppy blooming where ever we added it 
along with other things less desirable.

But I was naive and hopeful and planted my bulbs: Bloomeria crocea, 
Brodiaea californica, B. elegans, Brodiaea stellaris, Calochortus 
uniflorus, Dichelostemma capitatum, Triteleia hyacinthina, T. ixioides, T. 
laxa, and Triteleia peduncularis. Then I waited for the show. Later I added 
a number of species of native Alliums, our rare Fritillaria roderickii (F. 
grayana) and over the years a few South African bulbs as well. Many of 
these natives grow naturally in nutrient rich clay that is quite wet while 
they are growing. Even though I get 60 inches of rain during our rainy 
season (November to May) I doubt this soil ever gets very saturated. Damp 

Most of the Alliums disappeared after a year. Allium unifolium lingered a 
year or maybe two before it died. Calochortus uniflorus which grow locally 
in wet meadows, probably in clay, never bloomed more than a couple of 
times. Often I saw no sign of it even though when I grow it in a container 
it not only blooms for months, but increases more than I'd like. One 
Brodiaea stellaris survived and bloomed most years, but none of the others. 
Triteleia peduncularis which likes wet spots occasionally was seen in a wet 
year. The same was true for T. ixioides. Some years neither bloomed. T. 
hyacinthina bloomed for a number of years before finally disappearing. The 
survivors were T. laxa which often bloomed in mass, D. capitatum which 
always had a number of blooms, but nowhere near the number you'd expect 
from all those corms I expected were in the ground. The Fritillaria 
surprisingly, was quite happy, blooming and setting seed most years. And 
some Zigadenus that found their way there did well too in spite of my 
observation that they often grow here in very wet spots. None of the 
Moraeas I added were very happy, with an odd bloom when you forgot they 
were there, but Tritonia crocata usually bloomed and Babiana villosa was a 

The bed was maybe eight inches deep (20 cm.) At least that is where the 
soil started out being. Every year there was less although I occasionally 
added bark mulch. To my surprise when I was digging up the bed most of the 
bulbs were at the one inch (2.5 cm.) level or perhaps twice that. Two 
exceptions: the Fritillaria was 3/4 of the way down and the Zigadenus was 
sitting on the hardware cloth at the bottom. So if these are plants that 
pull themselves down, why hadn't they? I suspect there was no great 
advantage to doing so. I doubt the soil at the bottom was wetter than the 
soil at the top. It is possible that with late less soaking rains only the 
top part got really wet.

This year we had a wet season with rain interspersed through the season and 
late rains as well. This bed looked quite nice. Once again I had blooms 
from the usual successes and the Triteleia laxa was quite nice. I think 
there is a picture of T. laxa from that bed in a good year on the wiki. But 
to my surprise this year there was bloom from T. peduncularis and T. 
ixioides which I thought were gone and even B. californica and Bloomeria 
showed up. Finally there was enough moisture to bloom.

When I dug out the bed, there must be many thousands of Dichelostemma 
capitatum. The Indians used these as potatoes, digging them up each year 
and eating the big ones and replanting the offsets. So I microwaved them 
last night. They don't have much flavor. I cut them up and added them to 
our salad after I sampled them and didn't tell my husband there was an 
extra treat in the salad. Afterwards I asked him how he liked them and he 
hadn't even noticed even though the consistency wasn't anything like 
anything else in the salad. He observed that there was something in the 
salad with a different consistency. Diana has reported that some of the 
Alliums and Calochortus are tasty, but perhaps they weren't as prolific and 
therefore not such a good source of food. I wonder if the Indians found any 
native "herbs" to throw in the fire to improve them. Some of them corms are 
quite large. On the other hand all of the Triteleia laxa were small. That 
surprised me since they were still blooming well. What I think are the 
Brodiaea elegans too are not very big. Obviously the lack of fertility in 
the soil (I'm very lazy about fertilizing raised beds) made a difference 
since corms of both of these when I repot are much bigger.

I have grown Alliums in my redone raised beds in containers with my 
planting mix which is Orchard Supply bagged soil (fir bark, sand, other 
things), with added pumice, sand, coir, often slow release fertilizer, 
ground up egg shells if I think of adding it. Planted in the very same kind 
of bed, but this time in containers with a different mix, they not only 
bloom, but return from year to year.

Mary Sue

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