Plant watering indicator

DETAILED DESCRIPTION I claim: 1.
Apparatus for indicating when a plant requires to be watered comprising, a member insertable into the soil, said member having a layer of hygroscopic material disposed thereon wherein said hygroscopic material is mixed in a mixture with a material having adhesive properties, said mixture retaining the hygroscopic properties of said hygroscopic material, said layer being covered at least in part by a light transmissive cover, and said layer having a discontinuity therein for preventing evaporation of water from the layer located beneath said cover.
2.
Apparatus as claimed in claim 1 wherein said cover is a transparent plastic.
3.
Apparatus as claimed in either claim 1 or claim 2 wherein said colour of the cover and the colour of the member are different.
4.
Apparatus as claimed in any one of claims 1 or 2 wherein the member is elongate and substantially rectangular in transverse cross-section.
5.
Apparatus as claimed in claim 3 wherein the member is elongate and substantially rectangular in transverse cross-section.
6.
Apparatus for indicating when a plant requires to be watered comprising a member insertable into the soil, said member having a layer of hygroscopic material consisting of calcium hydroxide disposed thereon, the layer of calcium hydroxide being covered by a transparent plastic cover, said layer having a discontinuity therein for preventing the evaporation of water from the layer located beneath the cover and the colour of the cover and the member being different, and wherein the said hygroscopic material is mixed in a mixture with a material having adhesive properties, said mixture retaining the hygroscopic properties of said hygroscopic material.
7.
Apparatus for indicating when a plant requires to be watered comprising a member insertable into the soil, said member having a layer of hygroscopic material selected from the group, calcium chloride, sodium sulphate, magnesium hydroxide, calcium carbonate, alumena, polyethylene oxide, polyurethane oxide, tissue paper, cotton and woven textiles disposed thereon, said layer of hygroscopic material being covered by a plastic transparent cover, and the colour of the cover and the member being different, and wherein said hygroscopic material is mixed in a mixture with a material having adhesive properties, said mixture retaining the hygroscopic properties of said hygroscopic material