Questions, questions
It is miserable outside! We still seem to be in a relentless system of low pressure off the Atlantic which means relatively mild weather but heavy showers of rain and strong wind with the odd bright spell as the winds wind themselves up in the west. Garden work is difficult because it is so wet. Even walking on the lawns (grass) seems to do damage.
Since I spend a lot of my time answering various questions for people it seems logical to revisit some of these and restart the ‘Question of the week’ category – on the right. So, for a while, I will deal with some of the most common questions I get asked. I will not deal with hydrangea flower colour (again) because I have dealt with it so often. You can get the answers to that one here.
So here goes:
Planting under trees
Someone had three silver birch planted when their house was built. They complained that other houses only had two! The trees were shading the ground beneath and this was making it difficult to plant.
While it can be difficult to plant under trees because of the shade and roots that will suck up moisture, there are lots of evergreens that, with some initial nurturing, will survive or even thrive. These include lots of evergreens including bergenia, viburnums, ivy, mahonia, fatsia, ruscus, vinca (above), pachysandra, lamium, liriope and nandina. Cyclamen hederifolium is another great choice.
The birches, though casting some shade, were healthy and provided a wonderful screen to provide privacy and it would have been a shame to prune them. Though birches can be pruned to thin the crown and lower branches removed to lift the crown you often see terrible pruning of birches, where they are cut off, at the same height and it ruins what are naturally elegant trees. Another answer could be to remove one of the trees completely to reduce the shade. It was difficult for me to recommend removing the trees since we should be planting more trees and while some trees do get too big for the average garden and threaten buildings or become a nuisance, birches are usually fine in all but the smallest plot.
Most of the plants that grow in dense shade are evergreen and have dark green leaves. They have evolved to grow in the shade of deciduous trees which are leafless in winter and so their evergreen leaves capture the sun that reaches them from November to March.
Rubus tricolor is a vigorous, evergreen groundcover shrub that is only suitable for large areas but has lots of appeal.
Spring flowering bulbs are adapted to this growing regime too, growing and flowering before the trees above come into leaf.
Planting under evergreen trees is much more difficult because the ground under them is dark and dry all year round.
When planting in shade, it is vital to prepare the soil well and to mix in plenty of organic matter. It is also best to plant in autumn so that the soil is moist for as long as possible after planting. If you try to plant in summer it can need real commitment just to water and keep the plants alive. It will still be necessary to water in the first summer, to help the plants establish but how much will depend on the weather and the amount of tree roots in the soil.
In some cases it can be best to avoid the battle and just gravel the area and have a few plants in pots – this is often the case below ‘Leylandii’.
Mahonias are useful in shade
This is one of a new series of posts based on real questions I have been asked. Feel free to add to the answers or include your ideas and experiences.
The Biking Gardener 
We are experiencing those dreadful conditions here in Waterford also with very heavy showers right through the afternoon – though the morning was reasonably good despite the fresh and chilling breeze. I have found birch create difficult conditions also and have used spring bulbs, among other things, but have found it a nuisance to move these bulbs/thin them out as the roots are so dense. I tacklet a clump of watsonias recently in this situation – with a pickaxe – but gave us before doing too much damage. Despite miserable conditions, the temperature reached 10C around lunchtime, the magic point when snowdrops open their flowers.
That must be a joy to have your early sowdrops (or are they late?). I agree that birch can have dense roots and they can also grow upwards! I once made a raised bed beside a birch (well about 60cm from the trunk) and after three years it was full of roots and was impossible to dig for the veg. We still have thunder and lightning and hail; maybe it will be nice tomorrow.
Snowdrops are at their normal season and very welcome. Like your raised beds I have snowdrops around the base of a birch and applied a good mulch of leafmould only to find it full of roots the following year. Hungry trees!
Much of our work here is under redwoods. They are the tallest trees in the world, and rather abundant here, so there is not much space that is not under them. Like all trees, they are shady and have greedy roots. Furthermore, their foliar debris has a pre-emergent herbicidal effect. It is how they inhibit competition. Many conifers do the same, including pine and cypress, including the Leyland cypress mentioned here.
A tough ground cover I have found very useful is Pachyphragma microphyllum, which although is listed as semi-evergreen in the A-Z, is evergreen for me. It has abundant white flowers in mid/late winter – spring. Looks good under Silver birch though it would swamp cyclamen, snowdrops or other small bulbs. It slowly spreads underground and self seeds if seed heads left on, but easy to dig out and spread around. Also useful to plant mid to back of borders to give very early interest when they are otherwise bare. Not very available to purchase but Mt. Venus usually stock and I both sell and give away plants.
I have never grown Pachyphragma macrophyllum. It is probably ignored because it is a brassica and I must admit that it would possibly be something I would walk if it as in a pot but I will keep an eye out for it now because it seems to be a good plant and I could use its attributes. It is apparently edible too.