MT Gardening

It feels like summer is almost here - and there’s so much to do!

I don’t know about your garden area, but mine is shooting all over the place as a result. Climbers have grown ten to the dozen, weeds are plentiful and the neighbour’s magnolia has left its spent flowers all over my patiotime for a clean through.

For this coming week I have set myself a target of topping up any mulched areas after first weeding through beds and borders. Once clear, I’ll add a good depth of organic bulky matter such as leaf mould; around 10-15cm should be fine. This has the benefit of reducing water loss from the soil surface, keeping those dreaded weeds at bay, adding nutrients over time, and as my soil is a silty-clay loam, it tends to cap if left uncovered. Soil surface capping is a layer or crust of compacted soil particles formed at the soil surface which may restrict water and air movement and seedling emergence (especially true if you are veg growing or trying to produce a hardy annual border). If caps are left to develop, they can impact on plant growth in the following ways:

• A soil surface cap can restrict the emergence of seedlings which results in poor germination rates.

• Water will run off rather than penetrating the soil and this causes soil erosion, which can expose plant roots or wash seeds or seedlings away which results in poor growth.

• Restricted gaseous exchange from the soil results in lack of oxygen, reduced respiration rates and poor growth.

In addition to mulching, I’ll be taking a good hard look at various plants to check their health and well-being… I’m looking for any pests and pathogens. As a keen rose grower, this month I’ll be looking out for the likes of rose black spot and powdery mildew.

Blackspot: A rapidly enlarging purplish or black patch appears on the upper leaf surface. The leaf tissue turns yellow around the spot and the leaf usually drops off. Small black scabby lesions may also appear on young stems and badly affected plants can shed almost all of their leaves and their vigour is greatly reduced. To control this I opt for a non-chemical control such as collecting and destroying all fallen leaves in autumn and spring and then pruning out all stem lesions in spring before leaves appear. I’ve done this already, however any leaves with spots on I’ll remove and incinerate. If you are using a chemical control any of the following fungicides would give some protection to your plants: tebuconazole, tebuconazole with trifloxystrobin or triticonazole.

Powdery mildew: A white powdery fungal growth appears on the leaves and shoots. Upper, lower or both leaf surfaces can be affected. There may be discolouration (yellow, reddish or purple) of the affected parts of the leaf and heavily infected young leaves can be curled and distorted. Mildew growth may also be found on the stems, thorns, flower stalks, calyces and petals and heavily infected flower buds frequently fail to open. The mildew growth on all parts may turn brown as it ages. For controlling, use any of the chemical active ingredients above, or an alternative method is to water plants regularly during dry spells and mulch the soil with 10-15cm of well-rotted farmyard manure/leaf mould to conserve moisture. Feed regularly to encourage strong growth with high potassium-rich fertiliser. Badly infected shoots are best pruned out and disposed of as soon as the symptoms are seen. During spring, pruning any shoots showing large patches of mildew around the thorns should be cut out.

Lastly, for the first half of April, consider looking at the following tasks:

• Continue to weed between plants. I tend to use a hand trowel or fork as a last resort to take out any pernicious root systems such as creeping thistle or the spreading underground shoot systems of bindweed. I’ve started to add them to my homemade liquid feed production process. Check out this useful RHS link: www. rhs.org.uk/about-the-rhs/publications/the-garden/the-gardenback-issues/2013-issues/november/Garden-practice-Liquidfeed.pdf.

• Take care to double check all climbers and wall shrubs where limbs are flapping around untrained. Tie them in carefully using garden twine. With the likes of clematis, it is worth tying limbs round support systems such as obelisks. If they are later flowering types, I tend to shorten growth once tied in to encourage shoot breaks lower down the plant and hence increased flower numbers.

Here are a few other tasks for the month of April: www.rhs.org.uk/ advice/in-month/APRIL.

Happy gardening!

For any gardening tips please contact Tom Cole, Horticultural Lecturer, Capel Manor College, Bullsmoor Lane, Enfield, Middlesex, EN1 4RR, or send an email to, tom.cole@capel.ac.uk.