Healthy hedges start with healthy soil. Once your Living Wall™ is planted and settled, feeding and mulching become the key steps in keeping it vigorous, resilient, and looking its best.
At Twining Valley Nurseries, we take a measured approach: feeding enough to support steady growth, but never so much that plants are pushed beyond what their root systems can sustain.
Hedges are long-term plantings — living structures that rely on a balanced, consistent supply of nutrients. That’s why we recommend a complete, slow-release NPK fertiliser — sometimes called a controlled-release fertiliser — which provides a steady supply of nitrogen (N), phosphorus (P), and potassium (K) as the soil warms and plants grow.
This type of fertiliser is coated or stabilised so nutrients are released gradually in response to moisture and temperature. That means roots receive a constant, gentle feed over weeks or months, instead of a quick burst that can lead to soft, sappy growth. The result is sturdier, more balanced plants that are better able to cope with changes in weather and moisture levels.
Feed in early spring, when new growth begins, and again in mid-summer, when plants are actively drawing on reserves. Once a hedge has reached its mature size, a single spring application is usually enough to maintain its health and colour.
When planting permanent landscape hedges, it’s tempting to “enrich” the planting hole with compost or fertiliser. We don’t recommend it.
Adding rich material into a confined hole can create a pocket of moisture-holding soil that differs from the surrounding ground. Roots tend to stay within that comfort zone rather than spreading outward — and if that pocket becomes waterlogged, it can starve young roots of oxygen.
Instead, plant directly into the prepared soil, then feed and mulch on the surface. This encourages roots to grow naturally and deeply into the surrounding soil, creating a more stable and self-sufficient hedge.
After feeding, a layer of well-composted organic mulch (around 5 cm thick) completes the cycle. Mulch performs quiet miracles: it keeps the soil cooler in summer, reduces evaporation, suppresses weeds, and, as it breaks down, gently contributes organic matter and nutrients back to the soil.
Maintain mulch each spring, keeping it clear of trunks and lower branches to prevent rot and allow airflow. Over time, this practice improves soil structure, supports beneficial soil organisms, and keeps the hedge base looking neat and tidy.
Every complete fertiliser contains three essential macronutrients — each with a distinct role in hedge growth and resilience:
N – Nitrogen
Encourages leaf and shoot growth — the lush, green foliage that gives hedges their fullness and structure. It’s the driver of photosynthesis and the most visible nutrient in action. Too much, however, produces soft, sappy growth that’s more prone to frost, drought stress, and disease — one reason why measured, slow-release feeding is key.
P – Phosphorus
Supports root development and plant establishment, helping new plantings get their roots deep into the soil and improving resilience to dry periods. It also fuels energy transfer within the plant, driving growth processes from the ground up.
K – Potassium (Potash)
Promotes overall strength and health — enhancing resistance to stress, drought, and disease. It supports sturdy stems, good leaf colour, and balanced growth. In hedges, adequate potassium helps maintain form and density over time.
A balanced, slow-release NPK fertiliser supplies all three nutrients steadily, matching plant needs across the growing season rather than flooding the soil with soluble nutrients that leach away or overstimulate top growth.
Manure and compost are excellent soil conditioners — they improve structure, microbial activity, and moisture retention — but they are not balanced fertilisers. Their nutrient content is inconsistent, often low in key elements, and varies depending on source and composting stage.
Using them as the main food source can:
That’s why at Twining Valley, we recommend using well-composted organic matter as mulch, not mixed into the planting hole or used as direct feed. It complements, rather than replaces, a complete fertiliser.
And what about “plant tonics”?
Many plant tonics and liquid “boosters” on the market are supplements, not complete fertilisers. They can improve leaf colour or short-term appearance but often lack the essential nutrients in sufficient balance to sustain long-term growth.
Use them only as a complement, not a substitute, to your regular slow-release feeding regime. They can be helpful after stress (for example, trimming or transplanting), but they do not replace structured nutrition.
More fertiliser doesn’t mean faster or better growth. Overfeeding can lead to overly lush foliage that’s more vulnerable to cold, drought, and pest problems. Equally, fertilising in dry conditions can stress roots rather than help them.
A measured, seasonal approach works best: feed when growth is active and moisture is available. Once plants have established, the combination of slow-release nutrition and an annual mulch will maintain a hedge that is healthy, dense, and well-proportioned — without forcing it.
