Tuesday, 14 May 2019

Gardening Group Presentation on "Garden Looking after itself"

“My garden needs to look after itself” 
Quote by Jo Scott
Talk by Stephen Harding

Our group of keen gardeners met for the Monthly Meeting at Stephen's house. He had promised to give a talk with the title above. Here are the details.....
As much as we enjoy gardening and there are many benefits other than somewhere attractive to look at and sit in, a garden which will partially look after itself is a bonus.
·        Which plants survive the best in a clay soil?
·        Are there any plants which tolerate infrequent watering?
·        Which plants are best for ground cover?
We all face the same problem in this area – clay soil which is too sticky in Spring and Autumn and like a rock in Summer. Here is a newspaper article provided by Jo with a few suggestions.

You can see the full worksheet notes HERE

Key points:-
·        Sowing seed directly into clay is generally not too successful. This also applies to self-seeding plants.
·        Narrow window of opportunity for planting – Late Spring and early Autumn when soil is soft and not too wet.
·        Allow the worms to do the work. It’s probably better not to do too much digging. Mulching is better.
·        Clay soil is generally more fertile.
Mrs Gladstone says she achieved her lovely garden on clay by digging in coarse grit or pea shingle.
Here is what the RHS says about clay soil…….
When planting on heavy clay soil it is always advisable to attempt some improvement of the soil, by working in organic matter. Mulching the surface of the soil will also help improve the texture.
·        One of these materials is long manure (manure that still has a proportion of visible straw remaining) or composted bark
·        Finer grades of composted bark, leafmould, leaf litter, garden compost or mushroom compost will still have a beneficial effect, but to a lesser extent
·        Dig coarse grit into the soil profile is often recommended, but the quantity required to have a beneficial effect makes this an impractical solution on all but the smallest scale
·        When planting on clay soils, the bottom of the planting hole should be broken up before planting and the sides of the hole broken down using a garden fork. If not loosened, a sump may be formed in that water can collect, resulting in probable plant death from waterlogging
·        It is a good idea to delay planting on heavy clay soils until late winter or early spring, when there is less time for dormant roots to become waterlogged and cold
·        Mulch the base of the plants in spring with a 7.5cm (3in) layer of well-rotted organic matter which will help to retain moisture and suppress weed growth. Leave a gap of 7.5cm (3in) between the stems and the mulch to decrease the chance of rots developing at the base. Continually maintaining this mulch will gradually improve the soil profile
·        Freezing and thawing over winter of ground dug in October aids soil breakdown and helps to form spring seedbeds
So, have any of you had any success with the following?
Suitable plants for Clay
Berberis (evergreen and deciduous)Buddleia
Cotoneaster (evergreen and deciduous)Escallonia (evergreen)Fuchsia
Viburnum (deciduous and evergreen)Weigela
Ground-covering plants
Climbers and wall shrubs
Forsythia suspensa 
Herbaceous perennials
So, what are the plants that will survive best with little watering?
Here is what the RHS says about it……..
With some conditioning of the soil and careful watering, there is a considerable range of plants that can tolerate dry conditions once they are established.
Practical considerations
·        Plant any silver leaved, less hardy, sun lovers in April so they establish their roots well before winter arrives
·        Try to plant small specimens so that they get used to their growing environment gradually as they develop
·        Adding organic matter to the soil before planting can help to improve both water availability and drainage, but do not add fertilizer, as this can encourage too much lush growth which may flop in summer, require extra watering, and be affected by frost in the winter
·        Use mulches to retain moisture in the soil
Suitable plants
Many drought tolerant plants have silver or grey-green leaves, their light leaf colour reflecting the harsh rays of the sun. Some have a coating of fine hairs on their leaves or stems, helping to trap moisture around the plant tissues. Below is a selection of plants with good drought-tolerant properties.
This is a selective list. For full details of all drought resistant plants, please go to the RHS website  https://www.rhs.org.uk/advice/profile?PID=397   
Small shrubs
Artemisia ‘Powis Castle’(2ft x 3ft)Halimium: Height and spread variable according to cultivarHebe: Height and spread variable according to cultivarLavandula (lavender): Height and spread variable according to cultivar
Ozothamnus ledifolius  (3ft x 3ft)

Medium-large shrubs
Abelia × grandiflora  (10ft x 12ft)Callistemon citrinus: Height and spread variable according to cultivar
Elaeagnus angustifolia  (20ft x 20ft)

Campsis: 10m (30ft)Eccremocarpus scaber (10-15ft)Jasminum officinale: (40ft)Passiflora caerulea  (30ft)Solanum crispum: 6m (20ft)
Baptisia australis  (5ft x 2ft)Bergenia:  (1-2ft) x (18in-2ft)Euphorbia: Height and spread variable according to cultivarEryngium: Height and spread variable according to cultivarEchinops: Height and spread variable according to cultivarHeuchera: Height and spread variable according to cultivarOsteospermum jucundum  (4-20in)
Cortaderia selloana: (8-10ft x 5ft)Panicum virgatum:  (3ft x 30in)Pennisetum alopecuroides:  (2-5ft x 2-4ft)Stipa gigantea:  (8ft x 4ft)
Briza media
Pennisetum rubrum
Containers and borders
Half-hardy succulents
Delosperma cooperi
Hanging basket plants
Convolvulus sabatius
Pelargonium - trailing and zonalTropaeolum majus
And finally, how to suppress the weeds. Ground cover helps with weed control.
Here’s what the RHS has to say…….
Many plants are low-growing and spreading in habit and may be termed ground-cover, but the prime requisite of a good ground cover plant is to provide a rapid, dense cover, to suppress germination and development of weed seeds and to eliminate the need for weed control measures. Such plants are usually evergreens or have densely twiggy growth.
Practical considerations
Whatever ground-covering plants are used, some weed control will be necessary until the young plants have established and formed a cover (good soil fertility is therefore very important). They will also need to be kept watered during dry spells in the first season or two, especially if positioned under trees.

Suitable plants
Deciduous shrubs
Cotoneaster horizontalis 
Cytisus scoparius 
Gaultheria procumbens 
Genista hispanica:
Potentilla fruticosa ‘
Rosa Flower Carpet series: 90cm (3ft) apart
Evergreen shrubs:Berberis candidula:
Calluna vulgaris
Cotoneaster conspicuus 
Cotoneaster dammeri 
Herbaceous perennials:Alchemilla mollis
Bergenia ‘Morgenröte’
Cornus canadensis 
Symphytum ibericum 
Evergreen perennials:Epimedium perralderianum:
Persicaria affinis
Stachys byzantina 
Waldsteinia ternata:
·        Have any of the above plants been successful in your garden?
·        Have you had problems with any of the plants listed?
·        Do you have any further suggestions for plants that look after themselves?
·        Which of your plants survive the best with the least watering?
·        Which herbs and vegetables seem to survive the best with low maintenance?
·        Any other comments?
Stephen Harding