Sunday, May 4, 2014

How to make a bog garden, part 3. The planting.

So, here was where we were up to in the last post – ponds filled with peat and sand.

Today was the big day – starting the planting.

Before you plant, it is a very good idea to do a dry run with potted plants to sort out the arrangement. This may be a bit of extra effort, but it makes sense in the long run as digging up a bog garden is a lot of work (been there done that – twice!). So take the time and do it right!

Here is the bog for the non-red Sarracenia flava laid out in preparation for planting. This may look random, but it has been carefully arranged believe me! I will be putting maybe three or four divisions of several growing points each plant in the bog, not all the plants in each pot!

Here is a suggested planting layout for Sarracenia bog gardens. In the southern hemisphere, the sun is always to the north, so the tallest plants are planted on the southern end of the bog. This will stop them shading the shorter plants out. This is reversed in the northern hemisphere, where the sun is always to the south, meaning the tallest plants go to the north. In the photo of the laid out bog, the tallest plant I have – a S. flava var. flava I call “Helmut’s Giant” (after Australian Pinguicula expert Helmut Kibelis) – is on the southern extreme, with S. oreophila and some of the shorter S. flava at the front.

By this stage, the collection trays have some serious holes in them!

The first plants that went into the bog were the shortest – VFTs and some sundews, namely Drosera filiformis spp. filiformis, D. binata T-form, D. binata var. multifida (Blue Mountains clone), D. pulchella, D. pygmaea, D. x tokaiensis, D. nidiformis and of course, D. capensis. Here is the layout of the VFTs, with B52 at left and assorted red clones.

And here they are planted up. These plants are fairly straightforwards to plant, as their roots are chunky but thread like. A tent peg to poke holes in the bog was all that was needed. The method I use needs a plastic pipe or some other rigid pole that can be poked into the bog and will remain upright on its own.

Sarracenia, on the other hand, have very extensive root systems, and grow from a rhizome that branches across the soil surface. They need to be carefully planted and arranged.

Poke the pole into the bog where you want to plant your Sarracenia. Remember, they will be in the bog for longer than they would be in pots for, so allow for growth forwards for maybe four seasons when you position your pole (as a rough guide, my rhizomes grow maybe 20 mm in a season). Then dig out a channel or trench about 10cm wide in an arc around the pole, facing the direction of the sun (north in the southern hemisphere, and vice versa). It should extend all the way down to the gravel layer. Shape the peat and sand into a mound around the pole with nearly vertical sides, as shown.

Place no more than three or four divisions so the end of the rhizome buts against the pole, with their roots splayed out across the mound. Point each division so that its growth points will not converge on other plants. The mound should support the rhizome base and the roots, keeping the plants more or less in place. Keeping each rhizome level with the soil surface, scrape the soil back into the trench, gently burying the roots and packing soil under the rhizome. Most Sarracenia will bury themselves to varying degrees. I always keep the rhizome on the surface, but use the following method to re-establish the growth point correctly:

The pigmented areas of the growth points have been exposed to light, whereas the white areas have not. To re-plant your rhizome at the depth it was growing at, bury the growing point so that the white areas are underground, and the pigmented areas are above ground. Regardless of how you position the growth point, try and keep as much of the rhizome exposed as possible, as it promotes division and allows you to check on rhizome health without disturbing the plant.

The above techniques also work for pots. Fill the pot by a third, position the pipe maybe 1-2 inches behind the centre of the pot and build your mound out from the back of the pot to the pipe and building it to the top of the pot. Then position your rhizomes and fill the pot as above. 3-4 rhizomes per pot (maximum 8!) make a fine display, and the plants really do like being grown in clumps.

Here is where I had got to using the above methods by sunset – four clones of Sarracenia flava var. atropurpurea (FRT 1-1, FRT 1-1 x flava var. rubricorpora “Gotcha! Giant”, and two seedlings ex seed, Blackwater State Forest, Florida), two of S. flava var. rubricorpora (Gotcha! Giant, Reytter’s Clone) and one S. flava var. cuprea (Helmut’s rosy red), plus the VFTs and sundews.