From Sap Flow to Flowering

The Journey from Pruning to Flowering

As the chill of winter recedes and pruning secateurs are cleaned and put away, the vineyard starts to awaken, preparing for another season of growth and promise. Among the many varieties cultivated in the country, it is Chardonnay, Pinot Noir, Pinot Meunier, Seyval Blanc, and Pinot Gris that hold a special place in the hearts of Saffron Grange. Understanding the intricate dance of sap flow post-pruning and the subsequent vine development up to flowering is crucial for these grape varieties. The following blog delves into this fascinating journey, offering insights into our team’s meticulous care to nurture the vines from their dormant phase to the first signs of flowering.

The Importance of Pruning

As you will have learned from our blog on winter pruning, pruning is an essential viticultural practice carried out during the vine’s dormancy, typically between late winter and early spring. This process involves the careful removal of excess canes and wood to shape the vine and manage its growth. The primary goals are to regulate yield, improve fruit quality, and support the vine. Precise and gentle pruning is critical as it influences the balance between vegetative growth and fruit production whilst also maintaining and improving vine health.

Sap Flow: The Lifeblood of Vines

Once pruning is completed, the next critical phase is the onset of sap flow. As temperatures begin to rise, the vines transition from dormancy to active growth. This period is marked by the phenomenon known as “bleeding” or “weeping,” where sap begins to flow from the pruning cuts. This sap, rich in water, minerals, and sugars, signals the vine’s reawakening.

Sap flow is driven by root pressure, which builds up as the soil warms and the vine’s roots absorb water and nutrients. This pressure pushes the sap upwards through the vine’s vascular system. For English vineyards, where spring temperatures can be variable, monitoring sap flow is vital to ensure that the vines are not stressed by late frosts or sudden temperature drops (more on that in a future blog post!).

Bud Burst: The First Signs of Life

Following sap flow, the next significant milestone is bud burst. The dormant buds swell and eventually burst open, revealing tiny shoots and leaves. This typically occurs in late March to early April, depending on variety and the specific microclimate of the vineyard. For early-budding varieties like Chardonnay and Pinot Noir, careful monitoring during this period is essential to protect the tender new growth from frost damage.

Bud burst sets the stage for the vine’s vegetative growth phase. The shoots elongate, and leaves unfurl, capturing sunlight and kickstarting photosynthesis. This period is crucial for establishing a strong canopy that will support the developing fruit.

Here at Saffron Grange, we undertake our first round of leaf removal, on the morning sun side of the vines, at flowering, as at this stage it pauses cell division for a short period of time which then results in less compact bunches developing, helping to promote air flow and the removal of fungal spores.

For a variety like Pinot Meunier, which has dense foliage, careful canopy management helps balance the vegetative and reproductive growth, ensuring that the vines do not become overly vigorous at the expense of fruit quality.

Flowering: The Culmination of Early Season Growth

Approximately 8 to 10 weeks after bud burst, usually in late June to early July, the vines enter the flowering stage. This is a critical phase where the future grape clusters are formed. The tiny flowers, arranged in clusters known as inflorescences, are largely self-pollinating. However, favourable weather conditions during this period are crucial for successful fruit set.

Flowering is a delicate process. Vines are particularly sensitive to weather extremes such as heavy rain, high winds, or sudden temperature fluctuations. For Pinot Gris and other susceptible varieties, these conditions can result in poor fruit set, known in French as “coulure”, or uneven berry development, termed “millerandage” or for the English vintners “hen and chicken” – essentially where grape bunches and berries are not uniform in size.

Specific Considerations for Each Variety

• Chardonnay: Known for its early bud burst and therefore requires vigilant frost protection. Its compact clusters are prone to diseases, making canopy management and fungal disease controls critical.
• Pinot Noir: This variety is highly sensitive to climatic conditions, requiring precise canopy management to balance its thin-skinned berries’ exposure to sunlight and protection from excessive moisture.
• Pinot Meunier: With its vigorous growth, Pinot Meunier benefits from early shoot thinning and canopy management to prevent shading and ensure good air circulation.
• Seyval Blanc: A hybrid variety well-suited to England’s climate, Seyval Blanc is relatively hardy but requires attention in canopy management and crop load to prevent disease and ensure even ripening.
• Pinot Gris: This variety can be prone to ‘hen and chicken’, making consistent weather during flowering critical. Canopy management is also important to ensure adequate light penetration and reduce disease pressure.

As the vines progress through these stages, our vineyard team works hard to remain vigilant, adapting our practices to the ever-changing weather conditions and the specific needs of each variety. This careful stewardship not only supports the vines’ growth but also lays the foundation for the season’s eventual harvest, promising wines that reflect the unique terroir of England and our particular site here at Saffron Grange.

The cycle of growth, from the first signs of sap flow to the delicate blooms of flowering, embodies the resilience and vitality of the vine. At Saffron Grange, we see it as a journey that celebrates the harmony between nature and human intervention, and these careful practices are what ensures that each drop of wine that we sell tells the story of its origins and the dedication that goes into it.