Lavandula stoechas Bandera pH trial

Lavandula stoechas pH-level Trial Influence of watering and temperatures

Lavandula stoechas Bandera Goals: 1) Check plant reaction and development on different pH levels in the potting soil.

2) Is there a difference in plant reaction between different quantities of irrigation and/or at different temperatures?

Lavandula stoechas Bandera • • • • •

Sow date: Week 04.

Tray Size: 288; 1 Seed / plug (at 19 - 20⁰C).

Transplant : Week 13 (27th March).

Container Size : 13 cm pot with 1 ppp.

Growing-on locations: • • •

• •

Container field, temperature average of 13 to 15⁰C. Tunnel, temperature setting at minimum 2⁰C. Moderate Warm Greenhouse, temperature setting at 16⁰C.

Used Soil with pH levels : ~5,5 – ~6,0 – ~6,5 – ~7,0 – ~7,5.

50% of pots DRY (only 50-60% water) and 50% WET (about 150% water) at each irrigation, only use clean water.

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temperature °C

Lavandula stoechas Bandera Tunnel 2014

30,0

25,0

20,0

15,0

10,0

5,0

0,0

average day°C Tunnel avarage night °C Tunnel

Temperature Day and Night in April, May and June @ Tunnel.

Lavandula stoechas Bandera Containerfield 2014 25,0

15,0

10,0

5,0

0,0

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temperature °C

20,0

average day°C Containerfield

average night °C Containerfield

Temperature Day and Night in April, May and June @ Containerfield.

Note : As ‘night time’ measurement begins at 6pm, the average temperature could be influenced by the temperature between 6 and 9pm and could be the reason for getting a higher night than day average temperature.

Lavandula stoechas Bandera # 5 Weeks after potting @ Containerfield.

Above DRY vs WET under.

pH 5,5

pH 5,5

6,0

6,0

6,5

6,5

7,0

7,0

7,5

7,5

Start yellowing at pH 7,0 and 7,5.

Lavandula stoechas Bandera # 8 Weeks after potting @ Containerfield.

pH 5,5

pH 5,5

6,0

6,0

6,5

6,5

7,0

7,0

7,5

7,5

Yellowing at pH 7,0 and 7,5 most visible.

Lavandula stoechas Bandera

pH 5,5

pH 6,0

pH 6,5

# 5 Weeks after potting @ moderate warm greenhouse.

pH 6,5

pH 7,5

Lavandula stoechas Bandera

pH 5,5

pH 6,0

pH 6,5

# 8 Weeks after potting @ moderate warm greenhouse.

pH 7,0

pH 7,5

Lavandula stoechas Bandera

pH 5,5

6,0

6,5

# 12 Weeks after potting @ moderate warm greenhouse.

7,0

7,5

Lavandula stoechas Bandera pH 7,0

pH 6,0

pH 5,5

# 5 Weeks after potting @ Tunnel.

pH 7,5

pH 7,0

pH 6,5

pH 6,0

pH 7,5 pH 6,5

pH 5,5

# @ pH 7,5 WET already plant loss!

Lavandula stoechas Bandera pH 7,0

pH 6,0

pH 7,5

pH 6,5

pH 5,5

# 10 Weeks after potting @ Tunnel.

pH 7,0

pH 7,5

pH 6,0

pH 6,5

pH 5,5

Lavandula stoechas Bandera

pH 5,5

6,0

# 10 Weeks after potting @ Tunnel.

6,5

7,0

7,5

Lavandula stoechas Bandera pH 7,5

pH 7,0

pH 6,5

pH 6,0

pH 7,5

pH 7,0 pH 6,0

pH 5,5

pH 5,5

# 13 Weeks after potting @ Tunnel.

pH 6,5

Lavandula stoechas Bandera

# 13 Weeks after potting @ Tunnel - pH = 5,5.

Lavandula stoechas Bandera Summary: •

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• •

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pH level of potting soil has for sure influence on the growth of Lavandula Bandera in growing-on phase; the higher the pH level will be (more Alkaline), the more difficult there is for the plant to take nutrients to them and plants become yellowish.

A pH level of 5,5 to 5,8 seems best for Bandera; higher pH levels do result in more yellowgreen leaves; a pH level of 6,5 and higher has really more negative influence on plant growth and development.

The irrigation level however, could maybe also be a more important point to watch out for; too dry results in grey-green leaves, no pot filling and slow plant development.

Too wet at the start results in more yellowing at higher pH levels, so a normal medium irrigation regime assures that the problems of yellowing due to higher pH level, will be less visible and plants do grow well and look slightly more fresh.

Different temperatures in combination with pH levels and a Wet / Dry situation doesn’t show extremely more problems; the plants only grow faster in higher temperature circumstances.

Advise: •

Use, for Bandera, a pH of 5,5 to 5,8 and an irrigation level which is between medium and slightly medium-wet (level 3 to 4) for best quality plants.